First thing to note is just make sure you do meet the requirements
now - as often if you've been out of education for a number years unis want to see (or even require) that you've undertaken some recent formal study. This could be an access to HE course, OU modules, an A-level or two or something else. Of those options the Access to HE course is usually the most straightforward and relevant option. This itself will help you adjust to returning to education - and Access courses are usually specifically designed to support students with this too!
Otherwise just try and be proactive, keep on top of things, make sure you attend all timetabled activities, make use of office hours as needed, and if there are any issues or concerns or problems - definitely flag them with your personal tutor as early as possible! If you're struggling with anything (academic or otherwise) it really usually does make a big difference to flag this up early as they can then often try and help you troubleshoot things to help you improve
One thing that does help with higher education in general, which may well be easier for you having been out of education and, presumably, working, is treating it much like a 9-5 job. Keeping a consistent schedule to go up to campus and remaining there working on your assignments, doing readings, doing various "admin" tasks you need to do at uni, and attending all your timetabled activities can make a big difference - even just in trying avoid major "crunch" and stress and anxiety that go with that, and helping you hopefully maintain a "work"-life balance with your studies.
It's easy as a student to find it hard to "switch off" and end up having a constant low level stress of worrying about bits of work you feel you ought to be doing while trying to relax - if you maintain regular "hours" this can help a lot as you can think "actually yes I've done my hours and worked on all my stuff consistently through the day so am happy to take some time for myself").
Also once you're at uni definitely see if there's any specific targeted support for mature students or those from non-traditional educational backgrounds - often there can be some specific things available at unis which can help