The melody of Express by Christina Aguilera runs 488 notes across 54 bars, 3:17 long in Am at 112 beats per minute. The tab sits almost entirely in the first two frets, one note at a time — no chords to barre and no strumming pattern to keep up with. A piano backing track plays the chords and bass underneath, so the line you are learning sounds like the record even at half speed.
Prefer to strum and sing it instead? Express chords and lyrics.