Get the kind that are big and have a soft, fuzzy coating. The fuzzy coating is easier on your fingertips so you can roll the hot rollers quickly and without burning yourself.
First thing in the morning, plug in the heater, wait until the indicator says the rollers are warm enough (2 minutes?), roll them in your hair (5-10 min), then go eat and go about your morning routine. Your hair should be ready in 15-30 minutes depending upon your hair’s length, thickness, and if your hair was wet at all (this works best if your hair is very lightly misted with a spray bottle before rolling). Takes about 2 min to pull the rollers out. And, voila! Fluffy volume!
I did this for years and loved it. Recently, though, I discovered I could achieve similar results with a flat iron. If you pull your hair through and twist the iron just right, you can add waves and volume to your hair. Also, this will last me a few days. It’s not quick, though (takes about an hour and I have thick, waist length hair), and it’s a bit of a trick to get it right. But what I love is waking up the next day and all I have to do is finger comb my hair and it’s gorgeous. Zero maintenance.