If you're in a 4WD, I'd recommend taking the tracks from Bremer Beach lagoon, along Tooregullup Beach, Trigelow Beach, all the way to Point Anne Fish Hole to really make the most of the region. Point Ann and the surrounding beaches are stunning the explore, unfortunately you can't get any further east along the tracks as they have all been washed away - so you'll have to take the Point Ann Rd back to the highway from here to continue east.
If driving east to west, drive from the highway to Point Ann Fish Hole and you can drive all the way back to Bremer Beach.
Note: Point Ann is stunning, but if you're in a 2WD I wouldn't worry about it because the roads in and out are SO corrugated!
Unofficial - you can probably sleep on the beaches here, just be aware of the tides!