Hi Beth,
"Every great journey starts with one step"
It's a huge trip. I would break it down into small sections, just plan the first couple or so and adapt as you go.
You'll learn what you need and can live without.
I must echo the idea of starting in, say Bristol or Mindhead in September and walking round the South West Coast Path to Poole, Dorset.
There are three well written books - Trailblazer Guides - these will help you with your planning and give you loads of confidence. (I can lend you mine)
Maybe it's just me, I carry a tent and enjoy the peace of mind knowing that if I don't end up where I planned I can just pitch up anywhere in any weather. You'd be surprised how remote some parts of the coast are, with few people around.
I'd pack a survival bivvy just in case, just for peace of mind.
You probably need the same amount of stuff for a 4 day/3 night walk than you do for 30 nights, as you can wash, restock & buy on the go.
So a 4 day/3 night would be fine if you are planning to do a short practice run with your chosen equipment. Recommended.
You're choice of shoes are fine. I walk/run in Inov8 trail shoes, super light and comfortable.
Planning -
Hope for the best (dry weather, free stay in house, hot shower, home cooked meal, wine, chat & laugh with friends, place to recharge phone, comfy bed, hearty breakfast = re-engerised)
Plan for the worst (sleeping in bus shelter or worse, raining, wet, cold, no phone battery, injured, no pub, no local shop, poor nutritional meal, alone = ?)
Okay, sorry, I didn't want to paint a bad picture, but plan for that worst case -
- bivvy bag / tent, top quality clothing (tested out), phone battery pack, first aid kit, knowing your walking limits, google maps is your friend, carrying emergency food supplies.
Good luck with your dissertation.
There is plenty of expert knowledge and advise to be found amongst us on this site - you've come to the right place, with many of us already trodden where you are planning to go, albeit not in one go.
We all wish you well.
I live in Brighton, on the coast, so at some point you'll be passing by - you're welcome to crash, if you don't mind Zen, my dog
(yes I can provide all the above in the 'hope for the best').
We'd probably come and walk the next day with you.
Ian & Zen