Here's a tip to help. Get a non-permanent felt marker. With the bike upside-down or mounted to a stand, spin the wheel, then hold the marker against the fork near the rim, and slowly move it closer to the rim until the marker just touches the rim as the bent part passes it. Repeat this on the other side of the rim. Now you can just look at the marks on the rim and know exactly which spokes to tighten or loosen to move the bent area back towards the center. After you adjust the spokes, wipe the rim clean and repeat the process until the rim is straight. Finally, make sure no spokes were loosened too much.