Well length of time depends a what kind of bike... my road bike it takes a long time cuz the tires are so darn tight, but my P2 it takes under 5 mins.
Some helpful hits would be ... get a tire iron... plastic prefreably. I never used them a few years ago and always went at my tires with a screwdriver, but its really worth spending the 5 bucks and getting a set cuz then you don't havta be so careful putting the tires on (screwdrivers put holes in your tires right after you just patched/bought a tire). If you are too lazy/cheap to buy a set use the handles of butter knives. they are nice and round and fairly strong. Blow up the tire slowly if you are using an aircompressor, and make sure you got all the dirt/rocks out of the tire before you put the innertubes in. make sure the tire is going to rotate in the correct direction (its on the side of the tire), and thats about it.
Some helpful hits would be ... get a tire iron... plastic prefreably. I never used them a few years ago and always went at my tires with a screwdriver, but its really worth spending the 5 bucks and getting a set cuz then you don't havta be so careful putting the tires on (screwdrivers put holes in your tires right after you just patched/bought a tire). If you are too lazy/cheap to buy a set use the handles of butter knives. they are nice and round and fairly strong. Blow up the tire slowly if you are using an aircompressor, and make sure you got all the dirt/rocks out of the tire before you put the innertubes in. make sure the tire is going to rotate in the correct direction (its on the side of the tire), and thats about it.