Where to start?

I found a few good articles on here that broke down the process of what to do and when. I then copied it all into Microsoft Word and changed the timings to fit our 7 month planning time. We could then work down the list, delete anything that wasn't applicable to us, add anything specific to us, highlight tasks once complete and add our own notes. I found that better than the checklist on Hitched because I could personalise it more and have lots of notes for each task.

https://www.hitched.co.uk/wedding-planning/organising-and-planning/wedding-checklist/
https://www.hitched.co.uk/wedding-planning/organising-and-planning/ultimate-wedding-planning-guide/
I also had an Excel spreadsheet with all our budgets, quotes, deposits, outstanding balances, payment deadlines etc. It was helpful to see at a glance what total we were currently on and see values move from Quote to Outstanding to Paid.

I also had an Excel spreadsheet for our guests. It recorded when they got an invite, when they RSVP'd, which hotel room we had booked for them, their menu choices, any card/gift from them, if it was money/gift card what we spent it on and when they got a thank you card.

You will find websites that do most/all of this but I preferred having the ability to completely personalise it to what we needed, it was saved on a shared network I have with my OH so he could easily access it from his computer and it was easier to email things like menu choices to our venue.

I'm sure you will find ways that work for you, good luck in your planning.