Easiest (which is what 'for dummies' books are all about, right?) is as follows:
Get 1-3# of extra light/light DME
Figure out size of starter you need to make. Heat #L of water (just a bit over the starter size you need to make) to a boil.
Mix 100g of DME per 1L of water, with the heat off/reduced. Stir as you would when making an extract batch.
Boil wort for ~10 minutes, turn off heat and cover.
After 5-10 minutes start the cold water bath in the kitchen sink to cool the starter wort to a reasonable temperature. For me, that's in the 60's.
Pour chilled starter wort into flask, place on stir place, add stirbar, pour yeast in from packet/vial, and start stirplate. Cover flask with either a piece of sanitized tin foil, or use a foam stopper. DON'T use an airlock, you want a two way gas exchange.
When a nice vortex (it should be visible and at least an inch deep) has formed, and you're not tossing the stir bar to the side, leave it alone. Check on starter after a few hours. Then again after about 12 hours. By the time 24 hours has passed, on the stirplate, it should be finished. You can give it longer, but chances are it's done. The color will have changed to indicate it's done.
If you have time, cold crash the starter in the fridge 12-24 hours (or more if you have time) to get the yeast to flocculate out and form a nice cake in the bottom.
Decant most of the spent wort (use a rare earth magnet to hold the stirbar in), swirl to form a slurry and pitch said slurry into your oxygenated wort.
Questions??