Cauldron allows you to run both Forge mods and Craftbukkit plugins on your Minecraft server. Installing Cauldron consists of downloading the installer and installing a server locally on your computer, then uploading the generated/downloaded files to your server via FTP.
The steps are as follows:
Step 1: Determine the version of Minecraft you plan on running (this will depend on the mods you're running, etc.). Most mods & mod packs will display the necessary version.
Step 2: Visit this page and download the installer, server and CauldronBukkit for the respective version of Minecraft that you want to run on the server.
Step 3: Run the installer JAR file and install it to a folder somewhere on your computer. We generally suggest doing it somewhere on your Desktop.
Step 4: Run the installer 2 more times to ensure that all library files are downloaded; it will sometimes miss a few.
Step 5: Place the other files that you downloaded from Mae's web page and place them in the same folder that you installed the server to.
Step 7: Upload all of the contents from that folder to your server.
Step 8: In our Multicraft control panel, set the JAR file to the exact name of the JAR that appears as such: cauldron-VERSION...-server.jar
Step 9: Start the server. You're all set.