Trading microcaps carry a substantial risk. Let me say that again, substantial risk. You can lose A LOT of cash. Once again, A LOT OF CASH, LOST. Sure there is lots of upside, but there is also lots of downside. How much downside? Ever read about the Great Crash of 1929, WORST. You could be reliving it yourself trading these things.
So with that out of the way. You need to sneak into these stocks and sneak back out. Tip-toe. Depending on the volume, you might be tip-toeing in and out 100 shares at a time with limit orders. It may take you all day to build a position. Sitting there and seeing them execute 100 at a time.
Remember, everyone who trades that stock will be watching you on the Level IIs. They will see your order come in and go back out. Since everything operates so slowly, they will try to take advantage of you.
My advice is to stick with quality. Stay away from the microcaps. If you want some exposure to microcaps, why not just use an ETF?