We offer a guide to working with patches
on our wiki.
But before being able to consider working with patch sets, one must first set up a development environment
(if you're building for Android exclusively it is not necessary to build any of our source toolchains), and be able to compile Rockbox.
In the case of compiling for Android, this also entails having the Android SDK and NDK, and a Java JRE and JDK implementation (either Oracle Java 7 or openjdk-7 is fine) installed.
I have been considering making the process of setting up an Android suitable Rockbox build environment semi-automated, but I haven't had a lot of time lately and there are quite a few OS/shell specific considerations to take into account.
Setting up a development environment may seem like a daunting task, and indeed some people may find it somewhat challenging, but it is worth the effort for several reasons in my opinion. Primarily due to the fact that you would no longer be dependant on hoping that someone will be able to provide you with an updated patched binary if a feature you would like to test is introduced, or a bug that annoyed you fixed.
You could supply your own binaries as desired, at your leisure.
Secondarily for the sake of education and self discovery, there is vast potential for learning here.