If you are going to be pumping a lot, get a reallly good, electric, 2 breasts at a time pump! Medela makes a great one .
Your breasts will be full about an hour to 1 1/2 hours after you nurse, so that's an ideal time. Don't worry about not having enough the next round. If baby doesn't get enough, he will come back later! Or you can feed him the pumped milk by bottle.
1 handed, 2 breast at a time technique: apply one side, hold it in the crook of your elbow while you reach across to hold the other one. Then you use your free hand to read a trashy novel, gossip magazine or bounce baby in bouncer or sit and daydream for a few minutes.
Directions with pump will explain with pictures how to actually apply pump cups.
Hopefully this helps.
W. (Mom of 6,3,and 1 year old who breastfed for an accumulated time of 28 month of my life and pumped a lot too while working out of the home as well as while a stay at home mom!)