Velcro fasteners have been around since 1952, and yet their basic function remains the same. The hook and loop fastening is easy to use and popular in everything from shoes to organizational tools. Velcro does have its downsides, however. In time, the adhesive backing on Velcro can deteriorate, causing your Velcro strips to come off of the surface they once adhered to. Or, as many Velcro fans have discovered, the Velcro may no longer stick to itself. The good news is it doesn't take much to get your Velcro to stick once again.
Sew the Velcro back on. If the Velcro is on an item of clothing or a shoe where you can sew it back on, then this is likely your best and longest lasting option. Just use a running stitch around the edge of the Velco in a colour that matches your fabric or the Velcro.
Glue it back on. Hard surfaces such as wood or plastic may require the use of a heavy-duty glue. Choose a glue that suits the surface. An instant adhesive (like Krazy or Super Glue) will work on metal and plastic surfaces, but use a wood glue on wooden surfaces.
Try a different Velcro product. Velcro manufactures industrial strength products tailored for rough surfaces like brick, plastic and vinyl.
Clean the surface before you mount the Velcro. Rubbing alcohol is a good choice because it won't leave any residue that will cause the Velcro to fall off.
Brush both sides of the Velcro with the doll brush to remove most of the dirt that has accumulated in the Velcro. This is the likely culprit of your non-sticking Velcro.
Put the two sides of the Velcro (the hook and the loop sides) together and then pull them apart. Repeat this action a few times to remove more debris.
Coat the Velcro lightly with a spray of antistatic liquid. This will help keep the Velcro clean in the future.
Use proper safety precautions when using heavy-duty glues. Do not let the glue get on your skin or in your eyes. Use in a ventilated area.