Currently breastfeeding a 10 week old so my memory of the newborn days is fresh. Get a big sports bottle for water (so you can pull up the spout thingy with your teeth and drink one-handed) and always have it with you. In fact get two and keep the other one in the fridge so you can easily get another big bottle of cold water when you can't put baby down to fill it up. Take at least two bottles of water up to bed with you during those first weeks (the thirst is the worst in the first month, after that I didn't drink so much at night but still need a 750ml bottle now and drink most of it in the night)
Lots of snacks that you can eat one handed. I made/make granola bars as oats are good for your supply and they are very tasty. Make a comfy spot in front of the telly with remote, your phone, snacks, water, muslin cloths etc. all within reach. Lots and lots of muslin cloths in case you have a baby that spits up a lot (and if they do, holding them upright after feeds helps and don't burp straight away - I very rarely burp my baby and he doesn't get gassy but not all babies are like that, some need to be burped every time)
Cluster feeding is normal, and it can come back during growth spurts so don't be worried if baby suddenly starts wanting to feed all the time after they've been in a routine for a while. So long as they are wetting nappies and gaining weight then they are getting enough. They will lose weight at the beginning, more so than formula fed babies, so don't worry so long as it starts coming back after the first week. If you do get told to supplement because of weight loss always breastfeed on both sides first before you give the extra milk.
After the first few weeks consider getting a pump (just pumping once a day during baby's longest nap can build a decent supply, I've filled a freezer drawer already) to build up a freezer stash (but check that your milk doesn't get a soapy taste after being frozen as some people's milk does that - it's not harmful to baby at all but they might not drink it because of the taste) in case of supply issues later (supply can drop when you are ill for instance) and so that you can get a break (having some pumped milk in the fridge on weekend mornings means I can get a lie in while OH gets up with baby and feeds him a bottle - but don't skip feeds like that until 6 weeks when your supply will be more settled)
It is likely to hurt in the beginning (some people are lucky and it doesn't hurt at all - I was lucky this time but last time it hurt for the first two months, but the worst pain was the first two weeks) so lansinoh for your nipples is a god-send, and paracetemol if it hurts very bad (and if it hurts very bad get latch checked and check for tongue tie - probably good idea to get those checked regardless of pain). It will get better, and when it does breastfeeding will become so so simple and you will be glad you stuck with it.