There are two methods 1) pump and hold and 2) pump and release
1) pump and hold: You pump your btreasts until you feel a slight pull then stop. Wait until the pressure subsides and then pump a little more. Continue to do this through your session.
2) Pump and release: Pump until you feel pressure, slightly more than if you were using pump and hold. Hold this pressure from 2 -10 minutes then release the pressure for at least a minute and then re-pump. Each time you re- pump you should be able to increase your swell in the domes a TINY bit.
I believe anything from 20 minutes a day will be beneficial. When you first start try 10 minute or 15 minute sessions for the first week, then slowly increase the time. You can pump once a day or split it into two or more sessions, whatever best suits you and your lifestyle.
It is VERY IMPORTANT whatever method you choose to use that you listen to your body. Pumping should NEVER hurt. It is best to never allow your breasts to turn purple in the domes. Discolouration is normal, anything pink to red but any kind of blueish colour or blotchiness and you are over - pumping. This could actually damage your breasts and really not help you at all on your booby journey.
Slow and steady wins the race. Over pump and you will end up having to take time off which you don't want.
I hope this helps a little. I suggest you spend some time, when your noogling? Reading through the threads on this forum. I can pretty much assure you that every question you have about noogling will have been answered before. If not, then ask away!
Good luck and keep us posted on your results.