The Meaning of Life, the Universe, and Everything.
step 1, Open up minecraft and play the minecraft version of the mod (example orespawn is in 1.6.4 so play 1.6.4
make sure you open the world and wait about 5 secs
open up your browser
search minecraft forge
click the minecraft forge page (should be a bunch of minecraft version)
click the LATEST or RECOMMENDED versions
open up forge
install forge [if you didnt run the minecraft version in vanilla and then repeat]
now open minecraft starting page
click the arrow above your username
if you did instal forge right you should see something with the world ``forge`` in it
click it and play minecraft [note it should be vanilla] (note: now if you have forge or any mods installed minecraft wont accept crash reports if its an vanilla crash go to vannilla (selecting ur username) and crashing urself
now download a mod! some mods need backup mods to work!
now go to your Computer search (not internet) and search %appdata%
click mods (if you did not run forge just forge it wont be there but its ok just creat a folder called mods but dont rename it!