What You Need Before You Start
Sewing in extensions means braiding your natural hair into cornrows, then stitching wefted hair (hair sewn onto a thread) directly onto those braids using a needle and thread. The process takes two to four hours depending on how many rows you braid and how much hair you're adding. You'll need steady hands, good lighting, and patience—this is not a rushed job.
Gather these supplies before you begin: a rattail comb for parting, thread that matches your natural hair color (usually black, brown, or blonde), a curved needle (size 18 or 19 works well), wefted hair extensions, scissors, and clips to hold sections. A sewing kit from a beauty supply store will have most of what you need. You should also have someone help you—sewing the back of your own head is nearly impossible to do well alone.
Wash and dry your hair completely before starting. Braiding damp hair creates loose braids that won't hold the extensions. Your natural hair should be clean so the braids stay in place for the full four to six weeks the extensions typically last.
Key Takeaways
- Cornrow braids must be tight and flat against your scalp, running from front to back in straight lines, because loose braids will not support the weight of the extensions.
- Thread the needle through the weft (the thread line at the top of the extension hair) and then through the base of each braid in a continuous stitch, pulling snug but not so tight that you're pulling your scalp.
- Start with one or two test rows if this is your first time, because removing and redoing extensions damages your natural hair.
- Extensions typically last four to six weeks before they need to be removed and your braids redone, and leaving them in longer causes matting and breakage.
- Sleeping on a silk pillowcase and avoiding tight ponytails while wearing extensions reduces tangling and extends how long they last.
Braiding Your Base Rows
Divide your hair into sections using the rattail comb. Most people do four to six braids running from the front hairline to the nape of the neck, spaced about half an inch apart. The number depends on how much coverage you want and how thick your hair is. Mark each section with a clip so you don't lose your place.
Start with the first section at your hairline. Take a small amount of hair at the roots and begin a tight cornrow braid, keeping it as close to the scalp as possible. A cornrow is a three-strand braid that sits flat against the head—not a regular braid that hangs loose. As you braid, add small sections of hair from the scalp on each side, the same way you would braid a regular cornrow. The braid should be snug enough that you feel slight tension on your scalp, but not so tight that it hurts or causes redness.
Braid all the way to the ends of your hair and find each braid with a small elastic. The braids are your foundation—if they're loose or uneven, the extensions will slip and look unnatural. Take your time here. This step usually takes 45 minutes to an hour.
Threading and Stitching the Extensions
Cut a length of thread about 18 inches long and thread it through your curved needle. Knot the end. Start at one end of your first braid—usually the nape of your neck is easiest because you can see it in a mirror with help.
Hold the wefted extension hair with one hand and position the needle at the base of the braid. Push the needle through the weft (the thread line at the top of the extension) and then through the base of your cornrow braid. Pull the thread snug—tight enough that the extension sits flush against the braid, but not so tight that you're pulling your scalp or the thread is cutting into the weft. Repeat this stitch every quarter inch along the entire length of the braid, working your way up toward your hairline.
When you reach the end of the weft or run out of thread, tie off securely with a knot under the braid where it won't be visible. Start a new thread and continue with the next section of extension hair, or move to the next braid. The stitches should be invisible when you look at the extension from the front—all the thread should be hidden between the weft and your braid.
Blending and Styling Your Extensions
Once all extensions are sewn in, take down the elastics at the ends of your braids and gently comb through the extension hair to blend it with your natural hair. Use a wide-tooth comb and start at the ends, working your way up to avoid pulling. The goal is for the extensions to look like one continuous length of hair.
You can now style your hair as usual—blow dry, curl, straighten, or braid. The extensions will move with your natural hair. If you see any braids showing or gaps between sections, you can add a few more stitches to tighten things up. This is also the time to trim the extensions if they're longer than you want, though most people wait a week or two to see how they settle before cutting.
Common Mistakes to Avoid
The most common error is braiding too loosely. Loose braids shift under the weight of the extensions, and within a week they'll be sliding down your head. If your braids feel loose when you're done, redo them. It's better to spend an extra 30 minutes now than to have extensions that slip.
The second mistake is pulling the thread too tight while stitching. This cuts into the weft, damages your natural hair, and causes pain. The thread should be snug, not strangling. If your scalp hurts while you're stitching, you're pulling too hard—loosen up.
A third mistake is leaving extensions in too long. After four to six weeks, the braids start to mat at the roots and the extensions tangle. Leaving them longer than six weeks causes breakage and damage to your natural hair that takes months to grow out. Mark your calendar for removal day when you install them.
Caring for Extensions Between Washes
Sleep on a silk or satin pillowcase instead of cotton. Cotton absorbs moisture and creates friction that tangles the hair and breaks the extensions. A silk pillowcase costs $10 to $20 and will double how long your extensions last.
Avoid tight ponytails and buns while wearing extensions. The weight of the extensions plus the tension from a tight style pulls on your natural hair and can cause traction alopecia (hair loss from constant pulling). Loose braids, buns, or leaving your hair down are better options.
When you wash your hair, use cool or lukewarm water and a sulfate-free shampoo. Wash gently and avoid rubbing or twisting the extensions. Condition the lengths and ends but not the braids themselves. Let your hair air dry or use a blow dryer on low heat. High heat can damage the extensions, especially if they're human hair that's been processed.
When to Remove Your Extensions
After four to six weeks, your natural hair will have grown out from the roots and the braids will start to loosen. This is the time to remove them. Waiting longer causes matting and damage.
To remove extensions, carefully cut the thread holding each weft using small scissors. Work slowly and close to the thread so you don't accidentally cut your hair. Once the thread is cut, gently unravel the braids and comb through your hair. This process takes about an hour. Your hair may feel tender or sensitive after removal—this is normal. Wait at least a week before braiding again to let your scalp recover.
If you want to reuse the extensions, soak them in cool water with a small amount of conditioner, lay them flat to dry, and store them in a clean, dry place. Most extensions can be reused three to five times if they're cared for properly.
Frequently Asked Questions
How much does it cost to sew in extensions?
The cost depends on where you have them done and the quality of the hair. A salon installation typically costs $150 to $400. If you do it yourself, you'll spend $30 to $100 on supplies and extensions, depending on the length and volume you want. Human hair extensions cost more than synthetic but last longer and blend better.
Can I sew in extensions on short hair?
Yes, but you need at least two to three inches of natural hair to braid. If your hair is shorter than that, the braids won't have enough to grip. You can also use clip-in extensions or tape-in extensions as alternatives if your hair is very short.
Will sewing in extensions damage my hair?
Sewing in extensions does not damage your hair if done correctly and removed on time. Damage happens when braids are too tight, extensions are left in longer than six weeks, or they're removed carelessly. Following the timing and care instructions in this guide will protect your hair.
How do I wash my hair with extensions?
Wash your hair in sections, working gently from the roots down. Use cool water and sulfate-free shampoo. Avoid rubbing or twisting the extensions. Condition the lengths and ends but not the braids. You can wash your hair as often as you normally would, but be gentle to avoid loosening the stitches.
What's the difference between sew-in and clip-in extensions?
Sew-in extensions are stitched onto braids and stay in for four to six weeks. Clip-in extensions attach with clips and you can remove them whenever you want. Sew-ins provide more coverage and a more natural look, but clip-ins are faster and easier to remove. Choose based on how long you want to wear them and how much styling you plan to do.