I can't download the gps track to locate whereabouts in the salt plains state park you go, but on the east side of the park there is access to the salt flats. Go south from Cherokee(hiway 58, 64) 4 miles, turn east on county road E0210 12 miles, there is a wide 1 mile access road the area where you dig for salt crystals.
the restaurant in downtown Cherokee has a good breakfast.
South of the lake is a free campground with water, restrooms, tables and firepits(lotsa wood available). North from Jet 6 miles(hiway 38) to the first curve, pavement goes east, road to camp entrance is west of the cedar fenced residential area, go past campground sign north for a short mile on a 2 track dirt road.
looks like this