2 lengths of course (long & short), it's a staggered start and timing is electronic.
The map will have a scale, legend and other info.
Control locations are pre-printed on the map, control descriptions too.
Descriptions give you the SI box number, e.g. control 1 might be box number '101', check it matches before you punch.
It gives lots of other info too.
You must visit control locations in numerical order.
They use a stick type SI card, you insert card in SI box, it beeps and away you go to the next one.
You'll need a map board, i use a
Miry one.
Most people make their own, a clip board cable-tied to handlebars and a couple of bull-dog clips or some such thing, google mtb map boards and you'll see loads of them
Mine rotates so I can orientate the map correctly on the go, definitely a good idea.
I don't measure distances when on the bike, mentally tick off any features you pass, such as junctions, a change in vegetation, large boulders, etc. to track your location.
Compass isn't 100% necessary, it's handy for orientating map, but you won't be taking any bearings, follow line features such as roads, paths, earth banks, fences, etc.
Check out
Route Gadget map of Djouce event from 2 weeks ago.
Pick short or long from drop down menu on right of screen and try pick out a route you might follow.
Have a look at the legend so you might be familiar with some of the symbols.
If you get a chance try out one of the permanent courses up around
Hellfire, Leadmines or Three Rock.
If you are trying these permanent courses go for a short or medium, they're designed to be done on foot and you'll probably end up carrying bike if you try a long one.
Saturday's event in Slade is designed for biking, the long will be tough enough (nav wise and bike/body wise).
Short is definitely handier, course lengths can be misleading, they're measured as the crow flies which is usually not manageable on bike.
You may end up cycling up single track and down the fire-roads, you might find yourself carrying your bike through a load of gorse, route choice is up to you.
The last two events in this league have been great, well worth trying it out, one time at least!!