Set reminders on your phone to refill your scrips as soon as you can do so. This will get you a few extra days of meds a month. Set those aside to cover your ass during delays.
Your pharmacist may be able to help you move things around so all/most of your monthly things can be done at once.
Keep a list of your meds on your phone. If you're worried that this particular provider is over sensitive and it might make you look overprepared, you can always drop in a line about how your your friend or relative insisted you do it, haha, but it really has made things easier.
Keep a list of every medication you have been given, when you started it, when you stopped taking it, and why you took it and why you stopped. This is especially useful if you are trying out different medications, like for depression or ADHD or whatever, and you wind up trying two or three or five different things in a relatively short period of time. You think you'll be able to remember the first one or two and don't need to write it down, but trust me, it is very possible he will need that information and not be able to remember it.
Jot down any phone call you received or place, and the name of who you spoke to, and what time the call occurred. Make a note of what was said.
Yes, bring people to appointments.
Have people there when you are on the phone if possible.
You can introduce them as your advocate, if you think that might be advantageous. This works better on the phone, where they should introduce themselves. In person, they should be dressed nicely, even if you look like crap. They don't have to talk for you, just be there. This made a huge difference when resolving my boyfriend's major issues at a psych clinic.
If you bring someone to an appointment and want them to come back with you, go up to the front desk and ask for a release that will allow them to do so. Some places aren't super strict about it but you still want them on the record for phone calls and such. Other places, such as GAC and reproductive health clinics, can be a lot stricter (for good reasons) and you will absolutely need the release.
Always ask how long a medication will take to work, and how long you should wait before contacting them if it doesn't seem to be working. This is an extremely helpful thing to know but they often don't remember to tell you.
When trying to get a bureaucratic problem fixed, always act as though you are just so glad to be speaking to THE person who can help you. Act as though they are the solution, make them feel appreciated. If all they can do is refer you to someone else, brilliant, they still did you a tremendous favor! I know it's really hard to be polite sometimes, but if you have a beef with a clinic or insurance company, but not the person you were speaking to, it doesn't pay to be actively rude. Even if you do have beef with the person you're speaking to, it still doesn't pay to be rude.
When dealing with red tape, always ask what the next step is, and whether you need to do it or whether they will do it for you. Know how long it should take something to be done, and check back in when that time arrives. Even if you have a really great relationship with a clinic, this is such a helpful thing to do for both of you.
Record all phone calls. Talker ACR and Talker ACR Helper, used together, will let you. Download them from app site, stores don't have them. Obviously, don't do this if it's illegal where you are. This is incredibly handy for reference, if you need to go back and check who you spoke to, ask a friend for an opinion, or see if they really said that absolutely batshit thing you think you heard them say.
If you are treated poorly and feel that you can do so safely without compromising your identity in a way that will lead to further poor care, leave bad reviews on major review sites, and encourage other patients to do so as well, if you know anyone in the same position. Google reviews are actually useful to people, they are one of the first places people check, but there are physician review sites as well. Leave reviews there. If you have multiple other patients leaving reviews, over time you can tank a clinic's rating. (Obviously do not have your entire friends group leave negative reviews over the same incident. That will lead to what you say being dismissed, and on some sites removed altogether.) If it prevents even one person from wasting their time or getting hurt, it's worth speaking out, especially if the issue is bigotry. I have avoided clinics and providers where homophobia/transphobia/fatphobia was mentioned, and considered that a bullet dodged.
With reviews, be clear right up front in the first line whether it was clinic staff or the provider that was the issue. Providers often work at more than one facility, so if you find out that this is the case it's perfectly acceptable to leave a bad review for them at that facility as well. I keep track of the couple of people who openly verbally abused me or who almost caused me harm, and make sure that bad reviews follow them wherever they go. Be aware you may be burning bridges, use discretion and possibly an account that is not attached to your real name. If there were identifying features to the encounter and you don't want them to know it was you, do not include those, or disguise those in a credible way. You can also wait a while. If they leave a response with the number of a clinic manager, consider calling them back. It isn't always helpful, but it can be super helpful if the clinic manager was unaware of what's going on.
Filing complaints with state licensing boards typically isn't difficult. Consider doing so if something truly egregious happened. Also, you can typically check medical licensing boards to see if there have been complaints filed or measures taken against a particular provider. Different kinds of provider may have different licensing boards, make sure you are looking at the right one for the type of provider you are seeing. If the professional does not appear on the licensing board website you may need to check a different organization, or even in a different state. The licensing boards are typically made up of medical professionals, so they are less likely to rule in favor of the patient than if they were patient-led as they should be, but a pattern of behavior, once established, can lead to future action and help others.
Do not threaten legal action. If that's the route you want to take, move in the shadows. If there's going to be a lawsuit, they should hear about that first from your lawyer. Don't give them warning, don't telegraph your actions. This is what a lawyer told me, so I'm assuming it's good advice.
That said, super politely asking for the name of the clinic manager or for regional/corporate headquarters can get things moving. It's a little aggressive, so take care with how you go about it, but a couple of times when I was in dire straits it was the only thing that got things done.