Fringe Activities outside the circuit includes Williams Fan Zone , (which is already inside the link you sent) you can also refer to this schedule for the when / what is happening in the circuit itself.

Other than to pack light / right, wear proper walking shoes and to stay hydrated throughout via the various water coolers around the circuit, I can’t think of much advice.

Which days are both of you attending and which areas will you you seated / hosted?
Saturday is generally a long day because of qualifying and there’s a drivers’ parade where the drivers will be driven around the circuit in vintage cars.

If you are looking at driver appearances, some folks will prefer to camp around the Zone 1 (if your ticket allows) Paddock entrance area but some drivers are more shy than others so YMMV.