This is what I do in a 50-over match.
When I bat, I tend to score a lot of fours early on (because of the field restrictions) and I never use the power button at all until the last 10 overs. I'd also practice using the power button in the nets, because I'm terrible at them, and have only hit one 6 successfully, and been caught using it once.
When I bowl I usually bowl the first 2 openers for 6 overs, then change to a spinner and a medium pacer for swing. Then I might put in a part-timer like lehmann and just keep bowling. Just bowl good line and length like the picture here, and you should get wickets.