AI tried searching but couldn't seem to find answer? I want to put a two tier cake on fondant covered board. Do stack and support on the board or transfer after stacked? I guess I decorate once on board? Any help appreciated :-)

I normally decorate the cakes individually and then stack them onto the cake board. Since my cakes are mud cakes and quite heavy once decorated, I'm too scared to transfer them to the board once they're stacked for fear of something going wrong at the last minute! If your cakes are quite light and they have good support systems in place, they might be ok to shift when stacked. You might need to have a trial run to see what you're comfortable with.

I would decorate board, then stack on board and decorate.. Just me though

AI'd say it depends on the cake. If you're worried about getting your baseboard dirty then place wax paper over the board so you can keep it clean.

I definitely would not build a multi tiered cake without it being on it's drum when you start stacking the cake. I made the mistake one time of doing this with a small two tiered cake, and when I put a huge spatula under the bottom tier to lift the cake onto it's drum, the cake circle underneath the bottom tier buckled the slightest bit, causing my internal supports to shift, which caused the whole cake to collapse about an hour later. Don't risk it.

If you're worried about getting your decorated board dirty, just place wax paper strips around the perimeter, and build on top of those. When you're ready to finish up the cake, pull them out and you'll be good as new.