1. Have you tested your modpack in singleplayer yet? If so, move on to #2. If not, test it.
2. Get the MCPC+ version for whatever minecraft version your mods require (e.g. the latest 1.6.4 MCPC+ if all your mods are 1.6.x)
3. Create a folder called server.
4. Put MCPC+ in that folder
5. Put a folder called mods in the folder called server
6. Put the mods in the mod folder
7. Start MCPC+ like you would start a minecraft server.