It might be the subject of a follow up article so I do not want to got into too many details.
I'll give you a clue... basically a rep has 4 phases:
Eccentric (lowering the weight)
Transition between eccentric and concentric
Concentric (lifting the weight)
Transition between the concentric and the next rep
So a rep can be adjusted first by changing the way each phase is done...
For the dynamic phases (eccentric/concentric) you can do it:
Superslow (moving as slow as possible, inch by inch but keeping it fluid)
Controlled (not trying to accelerate the weight, but not breaking it too much either)
Fast (trying to create a lot of acceleration)
Ballistic (trying to throw the weight or jump)
The transitions can also be modified to change the effect of a rep. For example pausing for 2 seconds between the eccentric and concentric takes away the stretch reflex which increases the need to produce force at the beginning of the movement. Or you can try to do the transition as fast as possible to increase the use of the stretch reflex.
And even the pause itself can be done differently... you can keep the muscles tensed hard during the pause which make the muscles get stronger isometrically at the position of the pause or you can release the tension as much as possible which forces the muscles to produce even more dynamic force to start the movement (this is a technique used in the Spotto bench press).
The transition between the reps can be used too... if you take a short pause before starting the eccentric phase of the rep you give the muscles a slight break and enable your body to get rid of some of the lactic acid. This will allow you to do more total reps but it will decrease the production of growth factors due to the accumulation of metabolites. Or you can do the transition without even locking out (for example on the bench press stopping one inch before lockout and going back down immediately) this keeps the muscles loaded and metabolites accumulate faster and lead to a greater release of growth factors.
That is the most basic way of building a rep.
The more advanced version is to add tension parameters. For example adding pauses DURING one of the dynamic phases... for example pausing for 2 seconds at the mid-point of a bench press when going up.
Another example would be doubling up part of the concentric phase (double contraction technique)... for example lowering the barbell to your chest, lifting it halfway up, lowering it back down, lifting it up completely... this is one rep.