What OS and version?
For Windows 7, the instructions are at:
http://windows.microsoft.com/en-GB/windows-vista/Create-a-network-bridge
A network bridge is software or hardware that connects two or more
networks so that they can communicate. You can create only one network
bridge on a computer, but one bridge can handle any number of network
connections.
1) Open Network Connections by clicking the Start button Picture of the Start button, clicking Control Panel, clicking Network and Internet, clicking Network and Sharing Center, and then clicking Manage network connections.
2) Hold down CTRL and select each network connection that you want to add to the bridge.
3) Right-click one of the selected network connections, and then click Bridge Connections. Administrator permission required If you are prompted for an administrator password or confirmation, type the password or provide confirmation.
BUT! There is an important warning at the bottom. So think carefully about the security of what you are doing.
Warning
You shouldn't create a bridge between an Internet connection and a
network connection because it creates an unprotected link between your
network and the Internet, which makes your network accessible to
anyone on the Internet.
UPDATE
So here's the thing, any network has resources on it that require protection. So when you bridge two networks together, you are often undoing or bypassing the security and control for BOTH of them.
In your case, you are trying to join one network to your university network, you are almost certainly breaking all sorts of rules that you have agreed to when connecting.
With what you are doing, you are allowing any machine on your own private network to connect to the university network without the controls that the university apply.