IMO a manager needs to make their direct reports and their team successful. But you can start doing that while you're an IC: get in the habit of unblocking people and generally being useful.
Also, manage a coop student or intern. One of the reasons companies hire them is to give their ppl management experience, so take advantage of that.
I did both of these things, and my company made me a manager 2 years earlier than when I thought I'd try to transition into management.
And after 6 months I decided I didn't really like management that much, and they graciously let me transition back to IC, haha.
It probably helps if your company is growing, has a healthy management culture, and great career progression options for ICs and Mgmt. If that's not the case, switch companies.