I don't want to give my trading platform away but if you want to trade on investorhub here, I don't know HOW they do it but you can set buys for 000001!
but other than that, get a platform that trades UBQU. buy typically 50K shares AT MARKET. it should say estimated purchase 5 dollars typically I catch nowadays 37500 of those for 1.87 and the last 12500 for 1.25 so you get 50K shares for 3.12 and 37500 of them at 00005
that's all I know, I've heard rumors some platofrms trade penny stocks at the 00005 level. I don't know for sure.