I found some cheap chopsticks that I use for dots. Next time you're in a sushi restaurant, try to get a few extra sticks. However, sometimes the sticks are not exactly round. As long as you get rid of the excess paint once in a while, the dots stay the same size.
Ah! Those dots haunt me! Especially when i need to do them by hand.
The only thing that I can add is to make sure that you have the right consistensy of paint if that is what you are using.
I have a bad habit of using it straight from the tube.