Most enduros have at least one day of practice. If you are able, practise the tracks in advance so you can have a look at each stage. It might make you a little bit tired for race day, but having a slight idea of where you are going will make a huge difference, which will serve you more than being 100 per cent fresh. Recording your ride with an action camera is a great way to review the race stages more than once without having to ride them all day. Watching each stage a few times will refresh your memory of those key areas on the stages that could be worth lots of time and might reveal a few good lines to smooth out some rough sections.
These five tips will help your day go a little smoother but the most important thing to do is have fun and enjoy it. The best thing is that you are out in the woods with a bunch of other like-minded people riding your bikes and shredding trails. Happy days!