I used sound mnemonics to learn on'yomi as suggested on the kanjidamage site but went through the kanji in the heisig order as presented in this site. I think the heisig order is worth following because it's well thought out and you can use stories presented on this site as a starting point. I occasionally consulted kanjidamage's on'yomi mnemonics list when I couldn't think of a good one. When you drill yourself, drill yourself on keyword > kanji + onyomi. This worked well for me. Also as you drill yourself, write each kanji next to each other on a piece of paper with no spacing. Then after you're done, practice reading out the on'yomi in sequence as if you're reading a Chinese article.

Teskal wrote:

Is there an Anki-Deck for Kanjidamage?

There is, you can download it inside Anki - the best one is by "umishock@gmail.com".