The simplest comparison we can make to define a hoof abscess is that it's like a whitehead pimple. And the fastest way to get rid of it is simply to pop it and let it drain; the pain relief is immediate because the pressure has been relieved. It usually starts with a localized, walled-off infection, which the body fights with white blood cells and inflammatory mediators. When lameness appears and how severe the lameness becomes will vary. Some horses might never get lame before the abscess ruptures on its own. So I advise you to be watchful at any symptoms. Treatment (or before treatment for you) requires cleaning the foot, locating the entry wound (if there is one), a palpation of the foot. You must be careful in face of debris because, they can cause causing further. A Good hoof care that leaves adequate sole for protection and develops a snug and uniform sole-wall junction is the best line of prevention. Good hoof care includes frequent hoof cleaning to remove rocks/mud and routine farrier care to keep the feet balanced and address any problems. If a horse has thin soles or is prone to bruising ... protect them with shoes, etc. And keep the feet trimmed so they don't get wall separations that can lead to white line disease and abscesses. Be proactive; don't wait for things to happen.
There is a good video (SmartPak) on youtube : https://www.youtube.com/watch?v=Nz9XIOVUBgk
Good luck, bye.