I have not done a ton of
VB like the most of the big dogs on the board, so let me try to help out here some.
1. If you are using a wheel or card, always circle the setter once you find out who it is by watching warm ups, or even after a rotation or two. Your veteran partner will help if you ask them! Then as you see more games, you will see how much the game revolves around the setter, even in JH/MS. Or even ask the scorekeeper who the setters are, they might tell you!
2. Get a good pen. Write on the top of your palm your captains (for each team), On the underside of your palm, note the numbers of the setters! Then refer to them during the game! You can take a look at your numbers as you are getting ready to call for serve when you need it. But make sure you try to find the setter on both sides. The more you do it, the easier it gets!
3. The light started coming on for me about half way through my 2nd year about where setters are, where they move, etc. It's just like other sports, do every match you can, and watch other people work with a card or wheel in your hand until you start to see patterns.
4. Get a book on
VB coaching, and team offense, or sit down with a local coach. There you will get a good introduction as to the type of offenses people run, and you will pick it up.
5. Setters reveal themselves quickly in a match. Find one, then look at the opposite player. If the setter is the RB, look to the LF. There you find the other setter if there are two of them, and rotations will get easier once you find the opposite of the setter!
6. In a lot of HS offense, at least in my area, you will see two players stacked , either on a wing, or in the middle. There are several reasons for this, the main two being clearing space on the floor for the two or three people who the team wants to receive serve, or to give the setter an easy path to the middle. As you go on, you will find that the setter is usually stacked in one of those places.
7. Like so many others have said, once you find the setter you will find where most of your trouble with back row attacks and IA's are. Keep track of these players, and life is good for you and you partner.
Just keep working at it, and digest the hints above, and you will start to see why it is so important to find the setter!