*Warm up first when possible.
*Make sure you're relaxed .. pull very easily at first until you can feel resistance disappear and that last bit of length stretch out .. pulling after that is hitting the right tissues instead of like Iron warned going backwards by just making everything tougher.
*(So long ago that I'd forgotten it .. have a 12 or 13 year history at this) I used to use a dry washcloth between hand and the glans for extra 'grab' when doing pulls and cranks. The grip was a -vast- improvement. I'd characterize the quality/texture of those washcloths as being 'cheapy' .. good ones might not grab as well. The cheapy ones were a bit 'abrasive' .. but the grip was kapow.
*Pull from different angles. 'Cranks' are the default concept for this, and I've done those forever, but also find that pulling strongly in a particular direction for 30 seconds, then a different one, etc, to be quicker gains than regular Cranks. Plus also mix in cranks too.
*Grabbing at the top at the glans, or grabbing halfway down the shaft, works different tissues. I find the best way to take advantage of this is to grab at the top at the glans with one hand .. and then to use the thumb of the free hand midway along the shaft to introduce varying angles and force-multiplying fulcrum-ing to the pulls. Hope that made sense.
*Maybe add some Cranks and fulcrumed angles ('Piss-Pulls' -- getting in some brief extra length exercises) several times a day .. like when you have to go take a piss. Gives you some additional stressor time-under-tension for the day and can be useful for prefatiguing before a Penis Enlargement workout.
*Look up Bundling, or someone that doesn't have to run explain it here .. you'll like it.
*Some final thing I wanted to say, dangit. Oh! DLD's Footlong Stretches. These are insane. You'll need to be of a certain amount of length or yoga-bendy-ness to use these .. and be SURE that you're warmed up and relaxed ... but wow, enjoy