Hi there,
LO was 4 months when they came home. The first couple of weeks were quiet-ish at home with visits only from SW and HV. We didn't really venture out of the house. DH had a couple of weeks off after intros so we mostly spent it being led by LO in terms of naps, feeding, play etc. We cuddled LO constantly, slept on us for all naps, fed on demand, lots of skin to skin, took lots of photos and just enjoyed that time before anyone else landed on us to see the new addition to the family. Be prepared to fend people off. We had to turn down a couple of events/visits much to people's disappointment in the first few months and it's still not forgotten even now I don't think.
In terms of family visitors our parents visited after two weeks. Stayed for a short time while LO was asleep and briefly after they woke up (snuggled up on me for the whole visit). No holding or cuddling and instructions really to keep a safe distance so as not to overwhelm. With everyone else it was a good six weeks or so before we had any other visitors in the house outside of my mum and SW/HV. We only went out to 'safe' places where we were highly unlikely to get caught by people who didn't know about LO. We got caught out once but it was fine!
You just need to be prepared to be very responsive, LO will be all over the place. The first few nights were hard because although the day seemed ok, as soon as it got dark it was almost like we could see LO looking around thinking 'where have my family gone'. It was heartbreaking but after a couple of weeks things were much more settled and relaxed.
Buy lots of food! Nice food ..... it was great not having to worry about popping out to get shopping. I'd second lots of calpol, ibuprofen, thermometer, baby olbas oil, muslins - a bogey sucker!!!! etc.
Choose some box sets. LO still naps a lot and was napping a few hrs a day at 8 months so you will have lots of time sat on the sofa unable to move until your arm is dead or you are bursting for a wee because you don't want to wake them!
In terms of routine, we found LO changed quite quickly. Maybe because of the massive change they had just been through but also because of their age. 8 months is huge in terms of their development. I think the key thing is to be as responsive as possible.
One thing to tackle as soon as they are home is registering with a GP and making sure they know that if you go to the surgery that LO is called under your name. They will be registered as birth name on system but you don't want them announcing that over the speakers when they call you. They will put a note on the system. We had a few problems with this and I had to constantly remind them. As first time parents to a young baby we were at the Drs a lot in the early days ....we worried about everything!
I have to say though, our first few weeks were quite wonderful in that our life just seemed complete. LO was perfect and settled reasonably well. We were very firm with people that they weren't to visit without strict permission and rules when they eventually did come round so we weren't bothered by anyone at all. That time on our own we will never get again and it was fantastic.
As for crying when buying stuff. I'm afraid that only gets worse once they come home. I cry at EVERYTHING now because we are just so lucky and it's just so lovely buying things I never thought we would be able to. I remember buying very gendered clothes (I know, I know!) from one shop when we were preparing for LO arrival and the shop assistant saying 'I bet I can guess what you've got' 
then asking all about LO. LO wasn't home by that point as we were a few weeks off intros but it was so strange talking about my child, it was very surreal but wonderful.
Our intros seem like they were yesterday but a million year ago all at the same time.
Congratulations!!!! Being a mum is amazing :)