You will need: A utility knife, a bucket for mixing, a rounded trowel, soapy water and gloves
Make sure you pick a dry day to patch your rubber running track surface.
Using a sharp utility knife, create a clean cut around the area you would like to patch. When cutting the area, make sure to cut the edges of the area at a 45-degree angle. This will create a stronger bond at the edges of the patch.
Clean the area of all loose granules and debris.
Pour all of the rubber granules into the bucket and mix the entire content of the binder in a plastic pail that you plan to dispose of later.
Mix the content thoroughly. Make sure that all the rubber granules are coated evenly with the binder
Using a rounded trowel spread the mix onto the area you are patching.
Use a mixture of water and liquid hand soap to lubricate the trowel after each pass.