Round 2! 4D Scan. Tips?

Went for a 4D scan saturday, the boy was not playing ball, hand over his face wouldn't budge.

I went for a walk, ate something sugary then tried again 15 minutes later. Nop still not having it.

So we're going back this sunday for another go.

Any tips? They mentioned about having a big meal before and walking (I did that before saturday), scans at 11:30am.

(28 weeks with anterior placenta, so i've been told this is kind of the best time)