You can encourage the let-down reflex artificially, by looking at your baby (or thinking about her), or by having a piece of her clothing next to you.
• Apply a warm wet cloth to your breasts.
• Massage the breasts in small circular motions around the perimeter of the breast.
• Gently stroke your breasts with your fingertips in a downward motion toward the nipple
• Lean forward and gently shake the breasts.
• Gently roll the nipple between your finger and thumb.
One hand expression technique is called the Marmet Technique,
http://www.lactationinstitute.org/MANUALEX.html
This is useful because it helps the let-down and so you get more milk.
(Please note that the diagram of the breast anatomy is out of date. Recent research has discovered that the milk reservoirs under the areola (the dark coloured part of the breast near the nipple) do not exist. The method, however, still works.)
Some mothers have found that the pumps are not good at getting the let-down to happen and so they use hand expression until the let-down and then swap to pumping. You can also use the times at the end of the Marmet Technique, including the massage, stroke and shake but instead of doing the hand expression use the pump.
Many mothers find that they feel fullest in morning. One trick is to feed on one side and pump the other side. If you can actually manage to pump the other side while the baby is feeding the baby will naturally make the let-down for you but this requires the baby's co-operation and often they move about too much.
The other thing is to keep trying. You will probably get more milk if you pump for 10 minutes every hour than if you pump for 30 minutes once every three hours. So if it is convenient keep pumping in short bursts rather than in marathons.
The following web page from the LLLI web site gives information about working and breastfeeding,
http://www.lalecheleague.org/NB/NBworking.html
Best wishes,
SARAH