Even tho you guy's say you're tired, it does sound like you are enjoying yourself. I teach IMC and have a UK MEP/IR and the instrument flying you do I think is the best and most rewarding of all.
The advice I would give is to prepare yourself properly before hand. Find out what you are gonna do the day before. Get the planning of the route and approaches sorted in plenty of time so you can sit and look at them for a while and act them out in your head on the ground as if you were flying or on MSFS. Great bit of kit for procedures I agree!
Get your cockpit management sorted. Nightmare when there's bits of paper and pens flying everywhere when you can't find what your looking for. Have some organisation.
Say Everything out loud. It may sound stupid as you are saying it but you wont forget to do it if you say it!
Good Approach brief, say it out loud so you and your Instructor both know you know what you are gonna do after you are Radar Vectored or just passed over the beacon.
I'm not gonna tell you how to fly the thing coz I'm sure your instructors are doing a grand job, just a few pointers that made my life easier when I did my IMC and IR.
Enjoy, and Hey what a felling when that runway is infront of you at 500ft after not seeing outside for an hour! Wayhey!! It works!
Good Luck to you all