Look, if you want to install a chain on a Campagnolo groupset without using any specialized tools or consulting the manual, it's not impossible, but it's not going to be easy either. You'll need to have a good understanding of bicycle mechanics and be willing to put in some effort.
First, make sure you have the correct chain for your Campagnolo groupset. You'll need a chain with the same number of speeds as your groupset. Once you have the correct chain, you'll need to thread it through the rear derailleur and then connect it to the crankset.
To connect the chain to the crankset, you'll need to push the pin out of one link and then reinsert it into the adjacent link. This can be tricky, so make sure you have a sturdy chain tool to help you with this step. If you don't have a chain tool, you can use a strong screwdriver or a hammer and nail, but be careful not to damage the chain or the frame.
Once the chain is connected, you'll need to adjust the tension. This can be done by shifting the rear derailleur and then adjusting the tension screw on the derailleur. Make sure the chain is not too tight or too loose, as this can cause problems with shifting and pedaling.
So, there you have it. A simple, straightforward answer that doesn't involve buying a $50 tool or watching a 20-minute YouTube video. But don't expect it to be easy. If you're not comfortable with bicycle mechanics, it's always best to consult the manual or seek the help of a professional. And if you think this is "rocket science," maybe you should stick to riding instead of wrenching.