A cool or drafty environment will slow down the rise time. When it's cool I'll often put a measuring cup of water in the microwave and warm it for 2 minutes. Leaving the cup in the microwave I'll put the covered dough in the microwave and close the door. You can also preheat your oven to 200°F and put the bowl in the oven after turning it off. Sometimes just turning the oven light on adds enough heat that helps your dough rise. I also love using a Raisenne Dough Riser.