Uncoiling a new rope: Hold it like it is a spool of rope and have a partner pull the rope from the spool stacking it in a random pile.
Coiling: Use a "backpack" or "butterfly" coil to avoid twists. To do so, stack the rope in the palm of your hand or behind your neck. Rather than looping it over your neck, go back and forth, putting a bight of rope on the one side, then the next. Cinch the rope in the standard way.
Twisted rope: Let it hang free and encourage the twist to unwind with your hand.
Rope bag: Between outings, store your rope in a rope bag to protect it.
Rope tarp: On climbing days, use a rope tarp to keep the rope clean while out in the field.
Logbook: Record all rope use in a logbook, especially your falls.
Things to Avoid
Nylon on nylon: This contact burns rope and webbing. You should especially avoid running two ropes through the same top-rope carabiners, and never run a top rope directly through slings.
Dirt: Use a rope tarp to minimize contact with dirt. Dirt works into the fibers and the sharp crystals can cut rope fibers, weakening the rope.
Stepping on the rope: This works the dirt into the rope.
Crampons and ice axes: Avoid direct hits with crampon spikes and ice axe picks.
UV rays (sun): Sunshine from day-to-day climbing is not likely to damage your rope. Too much sun, however, such as leaving the rope out for days on end for a fixed line or webbing at a belay station, can considerably weaken your rope. If your rope or webbing is becoming faded from the sun, consider replacing it.
Battery acid: Strong acids such as battery acid are extremely hazardous to your rope. Avoid them at all costs. (And it happens: Once after a great day of climbing with a friend at City of Rocks, I threw my rope into the trunk of his car. Once back at camp, I leaned into the trunk to retrieve my rope and noticed, beside it, a grocery bag covered in tiny holes that look like they had been eaten into the bag. My partner calmly exclaimed to me that it contained his spare car battery. Me, I freaked out!)
Poor rappelling and belaying: Fast or jerky rappelling, lowering and belaying can cause rope damage due to burning the sheath, as well as loss of control.
Marking the middle—not: UIAA tests of a few years ago showed that marking ropes with liquids such as those in felt-tipped pens can damage the rope; this even includes those markers sold specifically for marking ropes. Therefore, the UIAA Safety Commission warns against marking a rope with any substance, unless it has been approved specifically by the manufacturer of that rope. A bicolor rope where the pattern of the woven sheath changes halfway is another way to identify the middle of the rope.
Rope Cleaning and Replacing
Inspect: Inspect your rope often. You should be looking and feeling every inch of it for cuts, nicks and abrasions in the sheath, and for sections of mushy or flat core.
Washing and drying: Wash ropes by hand in your bathtub or top-loading machine using warm water and mild soap. Place the rope in a mesh bag to reduce kinks. Hang to dry, uncoiled, away from direct sunlight.
Storage: Store in a cool, dry area away from chemicals. Use a rope bag, hang it from a sling girth hitched around whole rope or hook the whole rope over a dowel.
Replacing: Ropes must be replaced when damaged or old. General guidelines:
Heavy sport climbing use with repeated falls: 3-6 months
Heavy trad climbing use with few falls: 1-2 years
Weekends: 2-3 years
Occasional use: 4-5 years
Huge falls or other damage: immediately!
Remember: Climbing safety is your responsibility. Expert instruction is absolutely essential if you're new to climbing.