Practice is the key. Its not too difficult to practice IMC flight in the UK because there are many days with broken cloud at 4000' or so. Check the map for controlled airspace, plan a route, remember the quadrantals, check the freezing level, and go and practice. With the cloud base that high, you can decend into VMC if you feel you've had enough at any time. I hope you will have remembered to write down the MSA for all the route sectors.
Planning a route well away from controlled airspace and high ground will reduce the stress.
Keep in practice or you will start to make silly mistakes.
Don't underestimate the benefit of using a PC based IFR simulator to keep up to speed on the proceedures and what the instruments should be showing.