If there is an old post about this, please someone direct me.

So I'm newly single and am on pof and Tinder, and am talking to several girls at a time over text, and am starting to meet and go on dates and even be intimate with some. I'm not looking for a committed relationship, just casual dating.

So my question is, does anyone have some good tips on how to handle a situation like this without lying? Like if girl 1 texts me asking what doing, and I'm actually spending time with girl 2... What do I say?