A practical guide for the partner who isn't the patient. What to do, what to say, what to skip.

Every appointment, every injection time, every monitoring follow-up. Don't make your partner remind you.
First consult. Retrieval. Transfer. Beta day. If you have to pick, those are the ones.
Get trained at the injection-training visit. Be the option, even if your partner does every shot themselves.
Stim cycles bring bloating and food aversions. Have things in the house. Make the call about dinner.
Laundry, groceries, walking the dog, replying to your in-laws. During stims and the wait, take what you can.
If your partner doesn't want to talk about whether you're having kids, you do the deflecting.
Trigger shot night. Retrieval morning. Transfer day. Beta day. If you don't know these are coming, ask.

Ask open questions, not yes-or-no ones. “How was the monitoring appointment?” gets more than “Was it okay?”
When your partner is venting, hold the urge to fix. Most of the time the venting is the point, not a setup for your solution. If they want input, they'll ask. A good response is some version of “that sounds really hard, tell me more.”
Watch for the days when your partner is quiet. Treatment is chemically hard. Sometimes they don't have words and a short text saying you're thinking of them is what actually helps.
A failed cycle, a miscarriage, a cancelled round, a result you were afraid of. Your job is to be present, not to be useful in the project-management sense.
You are not the patient and the patient's grief is louder, but yours is real and it matters. Letting yourself be fine when you aren't isn't loyalty; it's how relationships break under pressure.
Couples who get through this intact almost all say the same thing: they kept talking, and they didn't let the cycle become the only thing about them. Schedule a date that isn't a clinic visit. Take a weekend that isn't about timing. Be each other's people, not just each other's teammates on this project.
If you go on to have a child, you are going to need to be partners on the other side too. Don't let getting there be the thing that breaks you.