I don't know if there is a walkhrough. It is not too hard though.
Step 1: Gather a boatload (5 B) of credits
Step 1b: Have another small boatload (up to 1-2 B) of credits at hand for additional services
Step 2: Go to a carrier vendor system and buy the carrier. I don't remember the exact process, but I guess it will be in the station services menu
Step 3: You new carrier will be parked in the system if there is room, or in an adjacent system if the current one is full
Step 4: Either add the services you need / want right away, or do it lateras you need them. You do not need to be in a vendor system to add services, a carrier admin system will do. Those are more frequent and less crowded
Step 5: Park some more credits in your carrier's account for upkeep and market
Step 6: Either buy Tritium from a station and ferry it yourself, mine it, or set up a buy order and let players fill it for you for cash.
Step 7: You're done. Enjoy having a carrier.
As for the available services: I would say the bare minimum you might want is refuel, restock and repair. You do not need a shipyard or outfitting for yourself, the owner gets that for free. A bartender is nice to have to help with engineer unlocking, and also the bar is nice for immersion. Personally, I have repair, refuel, restock, UC, Vista and a bar on my carrier.