Measure the length and width of the damage. Cut a fabric iron on patch (in the dominant color of the chair fabric) one inch longer and one inch wider than the damage.
Fold the patch with the adhesive side facing out. Work the patch inside of the rip or hole and beneath the chair fabric, instructs Bob Vila's website. Use tweezers to spread the patch flat with the adhesive side facing up.
Arrange the chair fabric fibers or rip edges so the fabric lies flat. Trim away any jagged edges or threads.
Set your iron on the highest setting. Do not use steam while applying fusible patches to fabric. Test the iron on an inconspicuous place on the chair fabric to ensure the fabric can withstand the heat application. Synthetic fabrics will melt when exposed to a heat source. If the fabric is not suitable for ironing, proceed to the next step. If the fabric irons well, skip to Step 6.
Squeeze a pencil top eraser size dot of fabric glue onto a cotton swab. Lift the fabric around the damaged area with tweezers. Insert the adhesive-covered swab under the chair fabric. Wipe glue around the edges of the patch. You can also use extra chair fabric to make an identical patch. Press the chair fabric firmly onto the adhesive beneath. Allow the glue to dry before using the chair.
Place a pillowcase over the damaged area of the chair fabric with the fusible patch beneath. Press the iron over the pillowcase. Hold the iron firmly over the pillowcase and fabric patch for 45 seconds. Do not move the iron. If the hole or damage to the chair fabric was extensive, the patch beneath may be noticeable. A good color match between the fabric patch and the dominant chair fabric color helps conceal the patch.
Pinch the edges of the rip together. Trim away any jagged edges or loose threads. Thread a half circular needle with thread and tie a knot at the end. The Sewing and Craft Alliance suggests using curved upholstery needles wherever straight needle usage is awkward. Curved needles are useful for working on surfaces, such as chairs, where the fabric has little maneuverability and the surface is flat.
Insert the needle inside of the rip, pulling the thread until the knot meets the underside of the fabric.
Fold the edges under slightly if possible. Insert straight pins through the folds to secure. If there isn't enough give in the fabric to pull the sides of the rip together after folding under the edges, omit the folding.
Sew the rip together using a drawing stitch or a whip stitch. Sew two stitches at the end of your stitch line to secure the repair. Squeeze a fine line of fray stopping adhesive over the stitch line if you were unable to fold the edges under.