There isn't a guide, but there are some things you should do to set yourself up in a good position for further leave to remain in the future. If you haven't already done so, get your name added to utilities and the council tax. Make sure your bills/statements are sent in the post, and not paperless. Once you have official post sent to you, you can use this as proof of address to register with a GP (which will generate even more post!), and open a bank account in the UK.
Start saving bills, bank statements and other official documents that come to you and your partner. Over the next 2.5 years, you will need six pieces of correspondence addressed to each of you (if both of your names are on a piece of post, you can "share" it). Ideally, these will be dated 5 months apart, or as evenly spaced as possible. They must come from at least 3 different official sources (so, four electric bills, a council tax statement, and a letter from your GP would suffice).
Also, once you have proof of address, you can apply for your National Insurance number. You don't need the NI number to start working, but if you're applying for work through websites, many of them require you to fill in the NI number field to progress through the application.
You are permitted to drive in the UK for up to 1 year on your US driving license, if you have one. After one year, you will be treated as unlicensed. So apply for your provisional UK driving license soon, then take your theory driving test, some lessons, and then take the practical to get your full UK driving license before your right-to-drive-on-a-US-license runs out.
Any credit history you had outside of the UK does not count here. You will be treated as having no credit. You would be doing yourself a favour if you applied for an entry level credit card, made charges and paid them off, to build up credit. (I say this, but I've been here for 5-1/2 years and I'm still only on US credit.)
If you are under the age of 40, consider opening a Lifetime ISA while you can. The interest rate will be low, but the government will top up any deposits by 25% up to a maximum of £1000/year top-up. Note: Withdrawals can only be used toward the purchase of a first home, or for any purpose after you reach the age of 60, or you will pay a 25% withdrawal penalty.
https://www.gov.uk/government/news/lifetime-isas-available-from-6-april-2017