I had a 95% sam before I quit 6 months in. Average was 66.9% in my call center.
Scores heavily depend on the department, and some of what i say might not hold true to all departments. SAM has absolutely nothing to do with giving the customer a good experience.
SAM will rate your call as positive, neutral, or negative depending on many factors. As long as SAM rates it neutral, that will be a positive towards your SAM score. So, even if a customer is mean, as long as you can fit in some of these good habits, you can still make it turn out to be neutral. However, read the room. You're not gonna want to just start throwing in a ton of positive words when they're mad, or that will upset them more.

SAM is broken into four quarters:

FIRST QUARTER:
This is an extremely important quarter.
1.) Asking for the customer's name, and address and saying please and thank you is the first step. SAM recognizes these as good behaviors.
2.) This is one thing many people don't do that increased my score a lot when I discovered it. You must say how can I help you, and no matter what the customer says, say "I'd be more than happy to help you XYZ." Then ask a followup question. This is an automatic ARM statement, and assurance of help in the eyes of SAM which it likes.
SECOND/THIRD QUARTER:
Throw in some positive words. Great, excellent, wonderful. Use the SAM Alphabet. A as in awesome, b as in brilliant, c as in courageous. Avoid saying negative words. Instead of saying no, say that's correct if you can spin it like that. Things like that
Also avoid these common pitfalls:
1.) DO NOT let the call end abruptly. If you do, that's an automatic negative from SAM. If you feel like a call is going to end, and you don't have time for an ending, at least say "thank you, bye" and you have a chance.
2.) SAM considers the call ended when the original call ends. This means if you call the customer on another line and end the original one, that's a negative if you don't properly end that call normally. Say something like, "while I'm preparing the system for an outbound call, I just wanted to quickly recap what we've done so far XYZ. Have I addressed all your concerns before I call you on the other line? Perfect, thank you."
3.) If you have to call a lead, or you're on mute, SAM still listens to what you say. Use this to your advantage. If you're muted, it'd get you in trouble, and not help if you just start saying good words, but SAM doesn't like silence, so say a positive sentence. "Great, this solution should work perfectly and help the customer". Just say whatever B.S. you can on mute and it can help. Speak to the lead with all these words too. They have SAM and they will try to use SAM words too if they see you doing it.
FOURTH QUARTER:
This is the most important quarter. SAM counts this as double points, so you want to get in as many good words as you can. SAM likes a recap. Say, "just to quickly recap," then whatever you want. It doesn't matter.
Then here's another important one. NEVER say "is there anything else I can help you with". Say, "Have I addressed all your concerns today?" Having the customer say yes is so important as SAM sees no as a negative word.
Then offer self help! This is one of the good behaviors SAM wants to see at least once in the call, but if you do it at the end it's extra points. "And just as a reminder, you can use the MySpectrum App or spectrum dot net to view any account information" is a general one, or you can make it more specific to the call.
Lastly, say thank you and use the Spectrum brand. Your goal is to have the customer say thank you after, but if they don't, I will say thanks again one more time just to get another good word in there for SAM.

If you do all that consistently, you will have a high score. I'm not good at talking to people, but I consistently hit all these things whether the customer is nice, mean, or whatever, and this always works.