There's a lot of advice that can be given on surviving your tenure track years. The single most important IMNSHO is to learn how and when to say...
Junior faculty often have a hard time with this. They worry that saying no too often will make them look like poor colleagues and hurt their tenure chances. Certainly saying no to everything will do that. But saying yes to everything will also hurt your tenure odds. You won't have enough time to work on all that other stuff (grants, papers, teaching, more grants, more papers, more teaching, etc.).
And yet, junior folk will be asked to perform service (sit on committees etc.).* Especially if they're women. Especially if they're people of color. And if you're a woman of color? You'll be asked to serve on every imaginable committee.
How much is enough, how do you choose which things to do, and how do you say no to everything else?
In terms of how much is enough, ask. Often. Find yourself a senior faculty mentor if you don't already have one.** Ask them. Ask your chair. Do some digging and try to find out how much service work recently tenured folks did. It's really not hard to get ahold of people's cv's - they're often posted online. Or you could simply ask them.
What you choose to do is largely up to you. Yes, there will be those occasions when your chair/dean/senior person will ask you to sit on a certain committee because "it will be good for you"/"you're the right person"/they just need a warm body and everyone else said no. But you really do have a lot of control here. Say yes to those things that you care about and/or you think are important.
How do you say no? That's actually much easier than you might initially think. "I would, but I've already agreed to do x, y, and z." "That sounds like a great opportunity, but unfortunately it overlaps with [insert essential task(s) here]." "My mentor thinks I'm already doing enough/too much service and has told me to say no to everything else." *** Even "The tenure clock is ticking too quickly, I don't feel I have enough publications and/or funding, so I'm going to have to decline."
Yes, they're going to try to guilt/shame/beat you into doing things you don't want to and/or shouldn't be doing. Be strong. And polite. But still say no. Especially if you think what you're being asked to do is not suitable for someone without tenure.
Learn to say no. You'll thank me.
* I talk about service/committees here for simplicity. Learning how and when to say no is useful for many other things you'll encounter on the TT (e.g. unwanted collaborators).
** I cannot stress how important this is to your survival of the TT. Find someone who will be completely honest with you. Who will have your back if necessary. It's nice if their work is related to yours, but that's not as important as the previous two criteria. Really.
*** A good mentor will do this for you. And will take the heat.