Lol I used to Be in Your Spot......
1.Open Airport Utility
2. Click On your Wireless Device
3. Click Avanced
4. Click Port Mapping
5.Then Forward Your Port's
Notes: You can only forward one port at a time.
On my Mac I only needed to Forward port 28000
If you Have a Airport Extreme You will need a different Guide.
If You want me to Make a Detailed Guide with Pictures Your going have to ask Badspot if he will sticky it.