Permissions / Licences
Check the waterway access rights, as most UK inland (ie; freshwater, and many river estuary/harbour) locations require a licence of some kind for paddleboarding. Usually, no licence is required to paddle on the sea. There are of course exceptions to both of these ‘rules’ though!
For the SUP camping part of your adventure, make sure you know who the landowner is and that you have permission to camp. In some parts of the UK, an official campsite might be your only viable option.
Staying Safe
Safety is paramount. Arrange ground support if possible, or at least inform someone of your plans and when you’ll be back. Ideally, go with a buddy. Understand the weather forecast and water conditions, and always plan your routes accordingly.
Alongside an appropriate Safety Leash and SUP Buoyancy Aid or Waistbelt PFD for paddling, carry a reliable means of communication. Remember that mobile phones won’t always have coverage out in the wilds, so take a backup emergency comms device such as a personal locator beacon, sat-phone, VHF radio or similar. Everything needs to be fully charged, ideally with the means to recharge too.
Pack a first aid kit, and know what to do in case of emergency. Hopefully your own ground support can help. If not, you definitely need to know the local emergency procedures.