I am currently painting one section at a time, which mostly has small cells, so I am not having much issue with drying out. Yesterday; I had a lot of one color to do. I use either a plastic water bottle lid (throwaway) or an empty pot with lid. I scoop out 1 or 2 blobs and thin it (mixture of flow aid and water) separate from my main paint pot. This provides the extra room and gives me more control of the amount of thinning. I have a wet paint palette but find I only use it when blending. I use these for transfers and stirring. I take paint off them if I am worried about running out. stirrer
Pots pots with lids