Lift the front of the car so the steering rack doesn't have to do any hard work. Get ready for a little bit of a mess.

Actually, I removed the reservoir entirely. (I can never do this without making a mess.) I cleaned out the reservoir & set it aside to dry.

One hose from the PS reservoir goes directly to the pump. On the OTHER one, add some hose to a drain bucket or something. Idle the engine, turn steering full-lock back & forth a couple times, shut off engine. Don't run any longer than you have to.

Put it all back, fill it up, idle, turn steering back & forth. Now the fluid will be all foamy in the reservoir. Go have a beer while the foam collapses. Top up the reservoir & run it again. Repeat until it's not foamy any more. That's maybe 3 times?

Next time I do this, I'm probably going to drain from the cooler tube that runs across in front of the radiator. On the '98 Accord there's a real convenient place to disconnect that.