Personally if i had to relearn legato I would:
- start off with simple one string 'up and back' exercises to get my fingers used to the idea of it (triplets)
-Practice different patterns, making sure you incorperate all your fingers. (i.e using different variations of fingers to play the same exercise) Things such as substituting your 3rd finger instead of your 4th.
-My pinky is generally weaker then the other fingers, so for me to trill with it I find it harder. I have an exercise which helps build its strength. Basically using the 3rd and 4th across the strings i.e 1,2 (3rd finger, then 4th) and repeat that across the strings, before moving up to 2, 3, going back and repeating this pattern.
- Theres some great exercises around by
paul gilbert which explore the different patterns. Have a browse through them too, just get your head around all the different patterns which can be thrown at you.
-Don't forget
string skipping..
Just off the top of my head..if you want some useful legato exercises I would be happy to tab some of my favourites for you.
Im not sure what your playing ability is like so you might already know most of the above :P