Use a thermometer to gauge temperature, and never trust your finger. Make a fresh batch of food each feeding time and discard the unused portion to eliminate bacterial growth. Keep the unused dry hand feeding formula in the refrigerator. I used a syringe with a metal tube (See below) that are manufactured specifically for hand feeding baby birds, and can be found at various tractor supply outlets or Amazon.com. Hand feeding babies with a syringe is a bit more complicated than spoon feeding, which is safer but much slower and messier.
The above syringe is over 15 years old. It was by far the best syringe I have ever used. The only maintenance required was occasionally changing the rubber O ring. The stainless steel tube feeder never rusts but usually have to be replaced once in a while due to dropping it on the floor and breaking it. If you are a breeder with a lot of babies then this is the fastest and most convenient way to feed them.
I do not recommend first time feeders such as people taking their birds home early to use the metal tube device. First time feeders should spoon feed or use disposable, plastic syringes. Have the breeder you are buying the bird from show you how its done. You should feed the baby in front of the breeder at least two or three times before taking him home with you in case you have problems. A new baby coming home with a new owner will bond to them much faster with the slower, safer approach.
When spoon feeding, a baby Quakers lower beak acts as a little scoop, which I think makes them a little easier to feed than other species. When using the syringe method you must be especially careful to ensure that the formula is being guided into the crop and not the lungs, which will cause the baby to aspirate. For very young birds, the use of tubing attached to the syringe is beneficial in helping to prevent aspiration, as it guides the formula directly into the crop. With the baby bird facing you gently curve your hand around the back of the baby’s neck, grasping both sides of the beak using your thumb and index finger. Lightly touch the beak with the syringe until the baby opens his mouth. At this point you will elicit a feeding response, consisting of the baby bobbing his head up and down and seemingly jumping all over the place! Do not hold the baby so tightly that he cannot “bob” a little–this is needed to help him swallow the formula.
If you are pulling the babies from the nest box, the first day or two is probably the hardest when it comes to feeding them. That’s because they don’t know what a syringe is yet but if you gently squeeze the syringe with a few drops of hand feeding formula around its beak They might fight you a little at first but usually within the next few feedings they will be more than willing to open their mouths for you and eat.