Waiting is not something I'm very good at but when a spider needs to moult then there is no choice but to wait. There is nothing you can do. It (touch wood) has always turned out OK, there can be problems, but if there is then you are helpless really.
A little while back Marmite moulted, we found it on its back on a web when we got up already part way there. Marmite is beautiful with renewed glossy black hair. He/she/it is a small spider, about 3 inches across and the moult seemed over in a blink. Then you wait whilst they pump themselves up again - which can take a few days - when it's completed you finally get to see that all eight legs are there and intact.
Today we awoke to find Tiny, our biggest tarantula, on its back waiting to moult. Three hours later he's still there. We can only be quiet near the tank, make sure we do not bang, crash and thump about near the bookcase where his tank is and wait.
I am hoping that this moult will answer what sex Tiny is but as he isn't full size yet he could have more to go. I get excited to see what happens - will there be changes in colour density or size? Will we see male tibial spurs or it will it still be a game of wait and see?
I know spiders aren't every ones cup of tea, and I know a few friends that actually abhor them and will probably not read my blog for a while in case I post pictures, but I find them fascinating. I'm not into the OMG factor of owning them, what floats my boat is the fact that they are so separate from us and so alien. I can watch them for hours, how they move, hunt and groom is so weird it's compelling.