There are certain foods containing galactogogues that can help increase breastmilk supply, you can try pumping after feedings as breastmilk is produced on a supply and demand basis, you can contact your local lactation consultant for other helpful tips. If the above options don't help, you can always breastfeed your baby first (as long as you are producing milk) and then follow up with a formula or donor breastmilk as a supplement if needed. And remember, any amount of breastfeeding is better than nothing at all.