Round 1
For this round there are 6 dice. In this example there is a 6(a dice you want to get) and a one (a dice you need to get in order to qualify). Here there are 4 low value dice and two dice I want to keep. So I take the two I want and then re-roll the others.
Round 2:
With the dice rerolled, and there is a 4 (a die you need to qualify). This is the only notable die in the bunch so re-roll the rest.
Round 3:
Here you have a 5 here which is a good die so take that and re-roll the rest.
Round 4:
There is a 6 GREAT! Take that and since a three is in the lower half re-roll that.
Final Round:
Tough Luck. A one, you have no choice but to accept it here and hope for the best.
Some Tips
-Grab the One and Four as fast as you can.
-Always take any 6s you see, except if you are still looking for a 1 or 4.
-You are best off with only 5s and 6s in your final 4 dice. If you can help it don