First and foremost you need to make an advance directive (guide for Maryland), preferably with help from your doctor or a nurse regarding any decisions that might need to be made while you're in surgery. If you have someone you trust to make decisions on your behalf, you can authorize them (they don't need to be there during surgery as long as they can be reached on the phone). This sort of advanced directive is useful for ANYONE who does not have family to make medical decisions on their behalf, not just for people about to have surgery, but obviously is especially important if you are about to undergo a serious medical procedure. There are websites that will help you do this if you don't know where to start.
You need to plan how to get home from the hospital. If you can't arrange for a friend to drive you, you have to look into medical taxi services. Most hospitals will not allow you to leave in a regular taxi, and so you would have to leave "Against Medical Advice" if you were planning on a regular taxi, which in turn affects what your insurance will cover for post-op complications. However, it is generally possibly to find a medical transport that is actually cheaper than a taxi. Maryland Department of Health maintains a list of Non-Emergency Medical Transportation providers.
Check to see if your insurance will cover you to stay overnight in the hospital after surgery, or see how much it will cost out of pocket if insurance is not covering the surgery. The first night is the most difficult and it can be useful to have nurses responsible for your care if you cannot have a friend take care of you at home. A cheaper out of pocket option would be to hire a night nurse or home aide for the first night (or longer if you can afford it).
Post-op, you have to plan a recovery space for yourself, ideally near food, bathroom, water, and pain medications. Also any phone chargers, books, movies, etc. can be set up around this area ahead of time.
Pain Management
Buy over the counter pain medications ahead of time (confirm with your doctor or check online that these medications don't interact with anything you're already on- frankly you should check with your doctor what they are planning on prescribing you post-op for pain management and double check any drug interactions for that too online!).
Staying Clean
Plan and set up a wash station ahead of time, since you won't be able to take showers for at least a few days (generally around 5 days). Ideally this station allows you to rest in a comfortable position with easy access to a basin of water, soap, and towels.
Meal Prep
If possible prep and freeze meals ahead of time.
Mobility
You likely won't be immobile post surgery, but you should plan to expect extreme fatigue/pain for at least a few days just in case your body has a bad reaction to anaesthesia/surgery. Discuss with a nurse what they think your needs will be and use that information to inform your preparation (but also look online because your medical providers don't have the same insights as fellow patients).
Finally, create a plan of how you will get to your post-op appointments if you end up not being able to get there on your own. Also create a plan for how to get to the hospital in case of any complications.
Support
If you have friends that you know will be able to come help out, create a list of your needs and get your friends to sign up for particular items. This could be bringing food, coming over to watch a movie with you, doing dishes.
Contacts
Create a contact list of your doctor's phone line, a nurse hotline, and any other phone resources provided by your doctor in case you have questions once you get home. Place this list in an easily accessible/viewable place or have it on your phone.