Hi, if you can get a Haynes workshop Manual ( 0923 ) it covers the 1.4 i.E Uno. Which is what I assume, is the model you have?
It will explain how to remove the cylinder head, and have information on what torque the bolts should be etc..
It's fairly comprehensive, but as anyone will tell you in the UK these manuals always miss something out. So see it more as a guide, failing that it might be worth looking on eBay for a genuine Fiat manual that the Fiat dealers would use.
Hope that helps, an that you can your Uno fixed ��