What to do?

Looking for keywords for my site..

[cava]

Hey there I am currently re-design/developing my game site..

The question I have is what should I put for keywords and how many>

Eg. Should I put 20 keywords in meta or just 2-3?

I am not sure what is the best way to go about getting the keywords..

If I use OT should I pick keywords that have very high search results a month or the lower ones?

If I combine the OT & Google to pick my keywords if I do this

OT: keyword Game >> result 3 mil
Google: keyword Game >> result 50 mil

or

OT: keyword FlashGame>> result 200k
Google: keyword FlashGame>> result 700k

So for my site that is developed with and about Games / Flash Games what keyword should I pick? Game or FlashGame?

I realy don't know

If someone can give me few pointers that would be excelent...

Thanks

[Oskars]

3 keywords will be enough.
Optimize each page for 1 main and 2 second keywords (keyphrases).