Storing Air Shocks

I’ve swapped frames and have a frame with shock sat in a box, while I decide if I like the change (cheap Vitus Sommet frame). I’m enjoying the extra travel but not the over a kilo added weight and higher standover, due to a longer seat tube with a lack of seatpost insertion depth! I’ll give it a fair chance before I decide, so probably six months at least.

Do I store the shock fully aired up, empty or does it not matter?

Simply does not matter.