OK, I know how to separate the lights and darks. I even know about different water temps. That's not the point.
Here's how to knock it out. Buy the sheets that go in the washer and the dryer. They have the laundry soap for the washer AND the fabric softener for the dryer.
Use cold water for everything. Keeping the really dark stuff separate from the really white stuff is usually best, unless you're in a huge hurry and you don't care.
Hang up the t-shirts straight out of the washer if you don't want them to shrink.
Hang everything up right out of the dryer and you won't look like a wrinkled mess, unless that's the look you're going for.
There, you're done. You're welcome.