Quote from Babak:
fader, read the lessons (MaoXian) and it'll be clear. The only requirement for volume is that there be some!
I'm being facetious. Ideally you want a nice, deep pool of liquidity. Lots of trades/minute (this is what MaoXian looks for), tight spreads and you want it to continue for the morning. That is, you don't want it all of a sudden to drop off after the first bar or two.
This does not mean that 'dummies' relies on any sort of volume pattern. Rather, dummies requires that something be 'in play' and for that, it requires the attention and involvement of other traders - which translates into good volume.