This is important, to make sure your wishes are known, but it’s also to make your family and friends aware of your decision and the reasons for it. Supposing you are in the situation where there is such a decision to be made, it will make a hard decision easier if it’s already been discussed.
Also, my OH and myself have recently made sure that our organ donor registration is up to date. I thought maybe a lot of my bits and pieces wouldn’t be transplantable, but I was wrong. So we’ve now made sure that the organ donor info is sorted. I’ve also got the information for brain and spinal tissue donation, I just haven’t got round to doing it!!