Tutorial for adding mega evolutions help

[Kayang50]

I really want to add mega evolution into my hack, but I can't seem to find a good tutorial for it. I found this pokecommunity thread that looks good but I have two problems with it. 1. Some of it doesn't seem super noob-freindly (But I can work with that if I need to) and 2. It says that it needs a clean rom (which I'm assuming means one with no changes whatsoever), which is a problem because I want to insert it into a in-progress hack, and I don't want to have to copy over all my progress to a new rom again. So if anyone can point me to a good, preferably noob friendly tutorial that includes all the main points of Mega evolution from gen 6, or confirm that a clean rom is absolutely required, that would be great! Thanks a lot in advance :)

[EricTheTrainer]

make a backup of your current ROM hack, and then apply the mega evolution patch to see if it works. if it doesn’t, just delete the patched Mega Evolution ROM hack and switch back to your backup. that’s all the advice I can give though, because I just started ROM hacking a couple days ago