Ideally, you'd have the beer at about 65 degrees. If you can insulate it with a blanket or in a tub of water to help hold the temperature steady, that would be great. Temperature fluctuations can stress the yeast, causing some flavor impacts.
I have a little stick-on thermometer on all my fermenters. They are cheap, and you can tell at a glance if the beer is getting too warm or too cool.
I'm not one to keep the beer in the fermenter for a super long time like someone else mentioned, but I'd suggest keeping it there for at least two weeks.
After 10-14 days, you can take out a sample with a wine thief or sanitized turkey baster, and see if the beer is finished. It will start to clear a bit by then, and won't be so murky looking. Three days later, check the SG again, and if it's the same, the beer can be bottled.