Based on the riff from the Eddy Cochran song 20 Flight Rock this is wonderfully easy to play once you have mastered some basic techniques.
The first of these is the right hand damp - this is probably easier to achieve if you are not using a plectrum
- All you do is use your right hand index finger to pluck the open string and then touch the string lightly with the same finger to stop it vibrating.
This should be done to all the open string notes in the riff.
The second is the slide found on the second note of the riff
- To achieve this just press down on the third fret using your left hand 3rd finger - keep pressing down and move straightaway to the fourth fret.
Practice this to make sure you are getting both notes.
Thirdly using the correct fingers - Many beginners are tempted to use the left hand fingers that they feel most comfortable with, or find it easier using different fingering than that specified - this is usually a bad move as ultimately you need to strengthen all your fingers and stretch to get notes etc.
You should use the left hand third finger for the 3rd to 4th fret slide
followed by the left hand first finger for the note on fret 2.
Once you have the sequence of notes worked out practice slowly at first and gradually speed up .
Notice that once you have the riff worked out for the first pair of strings you simply move the riff to another pair to get the sequence - many riff based tunes work like this.