Dear @Fasto, please learn how to search, and how to read, please ><
As you see, this thread posted 18 hours ago have the steps here.
(and in regards to "how you tried searching around", this thread isn't even posted past the 24 hour mark [at time of writing]. You can't blame me for thinking you didn't search hard enough)
If you still don't understand either solution, I suggest you not try it;
not understanding either would suggest your technical level is not up to par, and you'll need even a small amount of technical skill (as well as ability to read and comprehend stuff) to use PKHeX and CFW related stuff properly.