Once you have pressed the syringe for the first time the thermal compound would probably leak from it continuously. Therefore, when you are moving the syringe over the laptop hold always a piece of paper under it so that you can prevent any possible leakage over the motherboard.

As you can see I haven't been very good at laying down the compound and I had to remove the excesses of thermal paste using a small plastic spoon (the one which comes with the GC-Extreme syringe). Nevertheless it still looks plenty of thermal compound in the picture. This is not the reality. Deposit only a small amount of compound!