Riders new to long-distance cycling are strongly advised to read these documents.
Regulations 5 Regs 6 and 7 are also relevant, and follow on from 5.
(The full body of AUK Regulations can be found here, but those not mentioned above are not directly relevant to rider conduct.)
Event Entry Form (nb, this is a .pdf file) includes some additional advice.
Ready to Ride advice from Simon Doughty, author of the Long Distance Cyclists’ Handbook, reprinted from AUK's Handbook.