Walking

I’ve done quite a lot of longish walks.
Some great advice already but for what it’s worth here’s a couple more bits:
I use a moisturiser on my feet (currently using flexitol, but used to use any old moisturiser) and I apply it every day. That keeps the skin supple, which in my case prevents hotspots and cracks.
Foot care is really important.
If you have the training time I’d suggest doing two longish walks or even three back to back. The first walk is easy but the second one if you do it immediately is tough and the third one tougher still. That really tests everything from socks to psyche.
I walk 25 miles in one day, and then walk back the next day, getting going as quickly as possible, no faffing around with breakfast. Eat snacks on the go. I eat dried figs dates and apricots and salty cheesy biscuits or crisps and fresh fruit. I avoid sugary snacks.
Change your socks. Try and do this really quickly, shouldn’t take more than a couple of minutes, then tie the old socks somewhere they can dry. If it pisses with rain that doesn’t work but putting dry socks on when your feet feel a bit clammy is so reenergising!
I am also in the habit of sending someone a voice message at predetermined intervals, I use FB messenger, record something about the route or how I’m doing then wait for a response. I then work out my reply and send it once I’ve reached the planned time/ location, and I keep a video diary on my phone. All that gives me something to do as I’m walking. Hope that helps!