Weaves give their wearer thicker and longer hair, but that hair should not have to come with lumps from the weaving method. Sew-in weaves can leave bumps, making your hair or head look uneven. There are ways to reduce the lumps from a sew-in weave without abandoning the method all together. Many lumps are caused by factors that can be controlled, such as the thickness of the track and the type of hair used, or by several issues stacking up. Take care with all steps of the weave process and your hair will be lump-free.
Create the tracks for the sew-in weave. Tracks are what anchor the sewn hair and a thinner track will leave less bumps. If you are braiding the tracks, use thin, horizontal cornrows that are snug but not so tight they cause damage to the roots. The braids should be smooth and flat to the head instead of sticking out. Lumpy braid cause lumpy weaves. You can also use braidless tracks if braiding is still too bulky. Pole weaving uses strands of thread to create a track and is better-suited for thin or fine hair than cornrows. Microbeads can be clamped into a horizontal row to make a track.
Use hand-tied wefts. There are two types of wefts and they come in various colors, and straight or curliness. Hand-tied wefts are created by hand, hence the name. Machine-sewn wefts are thicker at the top, where they have been sewn, and contribute to lumps with additional bulk. Hand-tied wefts are less conspicuous because the weft portion is thin.
Thread the hair needle with thread that matches the hair. Use enough thread to sew one entire weft. Anchor the weft to the beginning of the track by sewing it in the same spot multiple times. Three to four stitches are often enough. Any more and the thread may bulk up and cause a bump.
Sew wefts to the track by looping around the weft, not through. Line the weft up with the track next to where you anchored the thread and push the needle up from the bottom of the weft. Hold the the weft in pace with your pointer finger of your right hand, if working left to right, and use your other fingers to hold the loose thread aside while you work the needle. The curve of the needle will bring it up around the back of the weft and track, with the thread between the needle and the scalp. Sew evenly and snugly. Loose stitches contribute to lumps.
Close the row once your reach the end of the track by stitching in the same spot. Again, a huge lump of stitches will make the hair above it lump, so only use enough stitches to secure the weft. Hand-tied wefts can be finished several ways, if you have extra. If you know the length of weft you need, you can cut the wefts ahead of time and apply a drop of glue to the cut end. Hand-tied wefts must be glued if they are cut. Use a clear-drying, fabric glue and let the glue cure for eight hours before using. Wefts can also be folded over and sewn down. Be careful; doing so make ruin your lump-free weave if the folded end is too thick.