I'm not sure there is a single "best" way as much will depend on the image itself but this is where the various Scopes begin to earn their keep.
As a general approach you might like to see whether the Exposure and White Balance are O.K.
For Exposure I tend to convert the image to Greyscale and then use Levels while looking at Waveform to try to bring the Upper Limit to 100IRE and the Lower to 7.5IRE (to reduce clipping and crushing) and then remove the B&W Filter to see what has happened.
For White Balance I use the left eyedropper uinder the High and Middle wheels of Colour Correstor (place the High on a white/near white tone in the image and the middle one on a mid tone: you rarely need to use the Dark wheel but it might help).
Colour Curves, Saturation, Gamma and HSL may then need to be brought into play (and you may need to use Levels again as well) but remember to keep an eye on what is happening in the Scopes.
