Scrunch vs. Fold:
To ameliorate the fragility of the paper, users fractalize the surface, folding or scrunching to add a dimension of thickness and create an adequate buffer between one's fingers and one's filth. Scrunchers bunch the toilet paper to create a thick surface; folders take their time to neatly achieve the same effect.
Angle of Approach:
The anus is located in the butt; to access it, you have to either reach around your waist or between your legs. Reaching around requires a somewhat ungainly contortion of the body; reaching between runs the risk of contaminating your thighs with the used paper on the way out. Both problems, however, pose little risk to the experienced pooper.
For reasons of symmetry, reaching between is probably the more aesthetically pleasing choice. (For whatever that's worth -- in the bathroom, aesthetics are rarely the primary consideration.)
Direction of Wipe:
Centering the paper on the taint, you press and wipe up, scrubbing and collating and snowplowing all the filth onto the paper, exiting the area via the valley of the ass cheeks.
Or perhaps not. It's similarly popular to go sphincter spelunking, starting at daylight and moving downward, beginning at the pole and working your way south.
Most women choose to start down and move up and out, for obvious reasons. Among men, up vs. down is usually contingent on between vs. behind, vector of wipe following from angle of approach. Practically speaking, behind-and-up is the same as between-and-down: both are pulling the mess into a collection point. The converse is pushing, which is harder to control. Although pushing methods are not without adherents, they're also not without peril.
Saving the best for last, The Look Back:
With your anus clean, your poop is over. If you're not standing already, physiology dictates that you now do so. Society dictates that you flush. But for many, psychology intercedes, encouraging a look back.
Some look at their poop for signs of colonic dysfunction. Others look out of guilty curiosity, to see what horror their body has wrought. But for many, perhaps even most, the look is to take pride in their creation. In the afterglow of a successful movement, these proud poopers turn and face their demon -- once their tormentor, now their vanquished foe. If it's abnormally big, they feel pride; if it's unusually small, they feel disappointment; if it's terribly messy, they feel artistic. Whatever the case, seeing the poop is closure. The struggle has ended.
It seems contradictory that waste, which is by definition something the body used up or rejected, should engender pride. Poop is an amalgamation of the substances most useless to us. While it poses no threat to the person who created it, and thus should not be viewed negatively, why view is positively? Why should one not view it as a neutral fact of life, no more worthy of comment than breathing?
The simplest explanation of why people like to look at poop stems from the first duality of poop: the more it hurt to hold it in, the better it feels to let it out. To those for whom this feeling is positive, it's only natural to learn to associate the sight of poop with the euphoria.
