Thank you for this great post. Really good advice about keeping detailed records and getting professional help where needed. Another suggestion I would add is.....start doing your tax return very early so that you can assess your gains/losses well before the end of the tax year so that you can minimize taxes by adjusting your portfolio accordingly.
If anyone needs to do their UK Tax Return for 2018-19 which involves Crypto tax reports (as an input into your UK tax return), a good company which specializes in this crypto area is TokenTax and can be reached via the following link:
https://tokentax.co/?via=jas