You should not move during the attempt to WILD. But if you have an itch or need to swallow, try to hold up to see if the urge goes away. If it doesn't, do it, but slowly, as if you didn't even notice you doing it. It will not ruin you attempt, maybe just sets you back a minute or two. It's better to get rid of the itch, than be bothered by it for a long time.

An you can stay up for WBTB anywhere from 5-60 min. It can be different every time, but in general stay up until you can think clearly, but you still sleepy enough to fall asleep. During this time is important to wake up your logical mind, so something like doing math can help. And the more you thinking/reading about LDing, the better. Happy dreams