How to know when to flip the pancakes — After the bubbles appear, look for the edges to have a matte appearance. You'll also want ⅔ of the cooking to be done before flipping. (I actually like to use a flashlight when looking for the matte edge)
Don't worry about being too precise on the measurements of water and powder mixture. Instead, visually examine the viscosity after mixing (lift up the spoon/whisk, and watch how quickly the batter moves as it falls off), and add more water or powder, as needed.
Let the pancakes cool on a cooling rack, not in a stack.
Like putting cold water on noodles, this limits carryover cooking.
If you want to finish cooking before people start eating — keep them warm in an oven at its lowest setting, covered with a clean towel.
Use a light coating of vegetable oil. (often I use cooking spray lightly)
Let the batter rest for ~5 minutes after mixing it. If you don't do this, the leavening won't happen as much, and the first pancakes will be very dense.
Have your toppings (eg. butter, fruit, syrup) ready before you start cooking — you want the pancakes to be as fresh as possible when you eat them.