Knock off old patch and wire brush area to be patched and clean any residue inside hole. Home Depot has ReadyMix stucco patch, you will also need a small trowel or flexable puddy knife and some bonding agent to apply around hole with a throw away brush. Also a sponge and bucket of water to clean tools and clean up around patch.
Make sure you fill hole and even out flat to surface. Let dry for whatever instructions say on ReadyMix. Apply final coat and texture with the trowel to match existing finish. Prime and paint when dry.
Note, if you have some scraps of
sign foam around stick that in the hole if it is large so as not to have a large glob of stucco taking a long time to dry. Thin coats work better and faster drying.