Hey, Emma. Can help you out a bit as I've been doing the same thing!
You can always pop your axxie in a spare tub with tank water in it for the duration, mine loves a nice big clean cooking pan (it's colder for her). Just put her somewhere where she can watch the action (and stay away from the mad splashing!)
The best tip I was told is to dump your sand in a large container (a clean tub, pan, mixing bowl, washing up bowl - whatever you have handy, just make sure it hasn't come into contact with any chemicals like bleach, especially if it's plastic, as plastic absorbs chemicals used inside it). Dump all the sand you want to use inside. Now, fill the container up with warm or hot water and keep kneading through it (like you were making bread dough) to get all the settled 'dust' out. The water will get a little brown or have bits floating in it. Pour the dirty water away and repeat until the water comes clear. It won't guarantee no misty water but it'll greatly reduce how misty it gets.
Now, your sand will be damp. Beware when pouring it into your tank - it will splash as it 'flomps' into the water. Have a towel handy. Cover any electrical outlets and if you can have any nearby wires with 'fluid loops' (tie part of the wire into a U shape using hairbands or elastics to stop water going down the wire and into the sockets). After this, simply spread and enjoy! You don't need to remove water and I wouldn't really recommend it unless you have some pretreated and aged water handy. Just be aware that it will really splash when poured in, especially in a big tank.
I was worried for my baby because she was in a nursing tank with no substrate, so I bought her some sand to make sure she was chilled.
She pushes it out of the way and lies on the bare bit now >.< Cheeky Madam!
