Watch the D Lydian 1 online guitar lesson by Robbie Calvo from 50 Modal Licks You MUST Know
D Lydian is the 4th mode in the key of A Major, so I'll be focusing on chord tones of the IV chord D major 7.
In this first Lydian lick I am really pulling out the Major 7th sound in the chord by targeting and holding the note C#. I like how this sounds a lot because it's definitely not your typical approach.
There are a couple of nice intervallic ideas in this lick too that shouldn't be too hard to articulate. If they are,Isolate them,play them slowly until you can bring them up to tempo. At that point integrate them back into the body of the phrase.