My normal ride around me is constant rolling hills. Short ones. Only 25 to 50 foot and sometimes more. But never flat for more than 100 yards. So just I ride them. Pretty much the same thing applies to hills as does increasing speed. Every so often, wear yourself out trying to get up one as fast as you can. Which essentially is unstructured or informal interval training.
I prefer to keep a decent cadence around 80 to 90 rpm until I run out of a lower gear. But if you prefer to stand and run lower cadence that works too. It just tires me out more to stand.
Other than practice, weight is an issue. I just got a new bike that is almost five pounds lighter than my old bike. I'm already besting my times to climb from when I was in much better riding shape and condition four years ago. And I'm not even in my best riding shape for this year yet.
Do it safely though. Don't blast past others just to get a good time. Make sure it's safe and sane to get around them, otherwise, yield to them so you don't look like a jerk.