Hmm, you have the implements I've requested? Good... Lay them out nice and neat on the desk in front of you. Push the keyboard out of the way, you're not going to be using it for this tease anyway.
Now, stare at my luscious bottom for a few minutes, wouldn't you just love to be kissing it, worshipping it, licking your tongue all over my soft white knickers... Maybe later...
Pick up the first two elastic bands. I bet you know where these are going don't you...
Put them on the base of 'My' cock, right down by the balls. Make them tight, I want 'My' cock throbbing, aching and hard. Loop them around again if you need, make sure it's comfortable though. You'll be wearing them for a long time ;)
Are they on? Good. Hopefully 'My' cock is already starting to get hard and pressing against those lovely tight bands. Now you may stroke it, ten times, slowly up the shaft. No downward strokes yet, just ten lingering strokes up 'My' cock.