Don't worry big time. As long as you have a way to measure the temp and humidity accurately, your snake will be okay while you fiddle. If you're using a glass tank with a screen top, start off with heat lamp and small UTH or a more powerful UTH with no lamp (better for humidity) and a wet towel on top to hold in humidity. Measure what the temps and humidity are. if it's too hot on the hot size, go down in wattage on the bulb or get a lamp dimmer for it. If it's too cool, increase. Your baby will be okay if the temps and humidity aren't exactly perfect right away. They are animals, and nature is not a perfect keeper--there are times in their natural habitats when humidity would be a little low or temps would be away from the ideal. As long as it's not too cold to freeze or too hot to burn, just fiddle with it and don't worry. Snakes are quite hardy. Heck, many ball pythons live as pets in housing not suitable for them at all and, while this is bad for the snake's long term health, it doesn't kill them. Your guy will be okay for a few days while you mess with getting everything perfect. No big worries.