I use Dermatica and would recommend (although I haven’t used Skin&Me).
It’s a very straightforward process to sign up, and very flexible - the default delivery is every month but it’s easy to change delivery dates if you are not ready for another bottle or want to skip a month for any reason.
Here’s my link:
Try personalised skincare for just £2.90, plus £10 off your next month.
Head to www.dermatica.co.uk and checkout with code VY3WRV