I personally like to take out my initial investment once it has doubled and then I leave the rest in. Once that doubles take out another half and so on. Im not really into day trading tough to be honest. I think with day trading the margins you will be working on will be allot smaller. Allot of experienced day traders work on 5/7 very low percentage trades. They even go into the satoshi levels. Something I would recommend even if you don't day trade. There can be a very sizeable difference between 1cent and 2cents when thinking in terms of satoshi's