There is no universal schematic diagram for all bathrooms.
If you would have labeled the wires when removing the indiividual boxes that would have helped.
If you have a multimeter, you can test what you have. You probably have several supply lines that went to the individual switches. Now that you are combining into one box, you only need one supply line. Make sure that other supply lines that you dod not use are properly terminated in a box with wire lugs covering the ends.
Once you identify the supply you are going to use and other supplies with a meter, test the loads by temporarily connecting the source to one of the loads at one time. See which one makes the light come on, fan run, etc.
If you don't have a multimeter, you can buy an inexpensive one. If you need more information about wiring, get a wiring book. I got one from the local hardware store for $2.00. About 20 pages showing typical installation techniques, tips, how to keep within most codes, etc.