Most of the information about reservoirs can be applied to fishing natural lakes. Points, drop-offs, currents, weeds, bottom transitions, are common to both bodies of water. Granted, creek and river channels aren't found in natural lakes and there are other structural differences.
The biggest difference that I've found is that fish in natural lakes, with some exceptions, tend to stay shallower during the summer. Notice I said shallower, not shallow although there is usually a shallow pattern that will produce. Smallies are the exception as they can and are often caught at depths of 30ft. or more. Largemouth tend to stay shallower and 'deep fish' will normally stay close to the depth deepest weeds as that is where the forage will be on lakes that have an abundance of them.
The other big difference is the forage base in natural lakes. Bluegills, minnows, crawfish and smaller fish like bullheads, young bass and small perch are their main forage. That fact makes lure color choices a little easier, as natural colors produce well.