1) Set your picture style to neutral in your camera 
   
Doesn’t matter whether you shoot RAW or JPEG.  Set the style to neutral so you are in control of the post processing adjustments for sharpness, saturation, etc.   My standard post processing automatically includes some sharpening, saturation and contrast boosts, but sometimes I don’t what the standard. 
   2) Whiten teeth properly in photoshop 
   
Too many people photoshop teeth to bright white.   Here is a better way.   Create a new adjustment layer and set desaturate the yellows.   This will make all yellow in the picture grey.  Now paint on the adjustment layer mask so that ONLY the teeth have the adjustment applied.   This way the teeth lose their colouration but don’t shine out in artificial whiteness. 
   3) Whiten eyes properly in photoshop 
   
Same deal as above, do this carefully, I see far too many pictures where the eyes are completely bonkers. 
   4) Don’t sharpen everything 
   
Yes, the way digital cameras work is they are soft, they will need some sharpening.  But you can be selective about what you sharpen.  Usually the eyes need more sharpening, but the skin and background don’t. 
   5) Easy fix for under-exposure 
   
Duplicate the layer, set the blend mode to Screen, adjust opacity to taste.   I find this a very quick way to brighten an image without all the messing around with curves and levels. 
   6) Easy fix for over-exposure 
   
Same as above, duplicate the layer, but this time set the blend mode to Multiply, adjust opacity to taste.  Now this won’t recover blown out highlights, but again its a very quick fix. 
   7) Pixels are made to be punished 
   
As far as I’m concerned a picture is there to be perfected.  I have no compunctions about changing anything in the picture that needs fixing.   I will re-shape bodies, faces, and remove all sorts of blemishes and so on.  But.  At the end it must still be a portrait of the sitter – albeit one where they look their best. 
   8) Pictures should mean prints. 
   
Because a great picture deserves to be seen.   A print on the wall gets looked at, a bunch of bits and bytes on a computer don’t. 
   9) Put pictures in sequence 
   
Three (or five) very quick shots in sequence can tell a little story all of their own, maybe a bridesmaid dancing, a flower boy struggling up steps, children playing, make mini-stories using a quick series. 
   10) Use the golden mean 
   
Firstly most SLR’s shoot a 1 to 1.5 ratio image – it’s actually not a very pleasant rectangle. Much better to crop to an A4 format – which is proportioned to the golden mean.   Similarly, try and shift away from the rule of thirds and more to the golden mean, which means the third lines are slightly closer to the centre.