Youtube is your friend. Search there or search HBT....there are tons of resources out there.
Use mrmalty.com to determine the size of your starter. Basically, a starter is a small, very simple batch of beer used only to grow yeast. You need to use a 1/10 ratio of light dme/water. Boil it for 10 minutes, chill it, pitch your yeast. Stir plates are nice but not necessary...just swirl the flask every time you walk by.
You mentioned having a stopper and airlock....don't use em. You actually want oxygen to enter the flask to aid yeast growth. Just use a piece of sanitized foil to cover the opening.
I let my starters ferment for 1.5-2 days then I pop it into the fridge for approx 12 hours before use. Chilling the sample allows you to decant the "beer" and just pitch the yeast.
Go watch 100 videos (or just enough to feel confident) and then get to it!