Introduce yourselves to the neighbours as soon as possible! They will likely be interested to meet you too and it ensures you step off on the right foot with people you may see every day for a while!
Refrain from inviting people (unless they are offering to help) in the first couple of weeks until you have settled in/slept. But don’t leave organising a house party until everything is complete – people understand it takes time to move in and inviting people around forces you to step back and enjoy your new space.
When you have a house party – invite the neighbours (to make friends and pre warn them about the noise!) and buy lots of throw away cups/plates! Put everything out so people can make their own drinks then enjoy the night. If you’re really tired/overwhelmed – arrange for a cleaner to come and help with the tidy up the following day!