This exercise shows how to use the delay pedal to double the speed of your licks, quickly and easily. Adopted by Albert Lee within the country blues scene, by Malmsteen in the neo- classical world and of course U2's The Edge, this technique can add some interesting effects. Musically, I'm playing in the key of Em, so not too much to worry about there apart from  dorian / lydian runs and a short diminished part.
Throughout the exercise i am picking 8th notes alternately at 170 bpm, and setting the delay pedal to slap right back to create 16th notes - therefore the lick sounds twice as fast as it actually is! Setting the dealy pedal is probably the hardest part of this lesson -

Firstly delay time: Set a click or metronome to 125 BPM, and count 8th notes (1,2,3,4,5,6,7,8,). The initial note is on the count of "1", and the delayed note must come back on the count of "2and".In other words a dotted 8th note later. Easy enough if you have a winder - if you have a tap tempo delay it may take a little longer to get - try at 125bpm  first,  and use the backing track. If you pick alternate 8th notes, the delay should come back to make 16ths. This is demonstrated in part 1 of the video. When you are ok at setting the dealy at 125 bpm, try the higher tempo of 170bpm.

Secondly delay feedback: You need just one delay to come back.

Thirdly, delay volume: The delayed part needs to be the same volume as the initial note.

Try and play the lick with a staccato feel, by either palm muting or realising the pressure of the left hand slightly.
The lick firstly involves a sequenced descent in Em with some fairly large position shifts, then ascent in Em,  followed by an E Dorian descent, E diminished ascent and an E lydian descent to end.
This idea workes well for rhythm parts also (check out  The Edge from U2), but as demonstrated, also adds a different dimiension to your lead work, as long as it is used sparingly.

I hope you find this useful, and i'm of course open to any questions you may have. Good luck with it!

E minor

E Dorian

E Diminished

E Lydian