Yes you can use it right away, the donuts you tip will be deducted from the round earnings.
 Also there is a distribution ratio attached to each tip. The amount you tip is not really important, last round you got 123 donuts per tip you received. Hence a tip 1 of mine will be around 120 donuts at the end of distribution. So now you can just tip away and should still have plenty donuts at the end of the round.
We encourage everybody to use it if you would have normally upvoted via reddit.

!tip 1