You want to clean the rifle before you shoot it, any grease, preservative, or oil left in the barrel can severely damage the rifle if its fired.
Buy a 1 piece steel cleaning rod- stay away from the brass, aluminum, or jointed rods. Buy a bottle of Hoppes #9 (this stuff smells great) a .30 cleaning jag and bag full of cloth cleaning patches. Soak a patch in the solvent, stick it on the jag on the end of the cleaning rod, and from the bolt end of the rifle (refer to the owners manual on how to remove the bolt for cleaning) push the patch through the barrel. Then Push 3 or 4 more patches through until they come out clean and dry. Your barrel is now clean. Next, wipe down the bolt with a rag to remove any grease or crud. Dampen a cloth with a preservative (people prefer different products like CLP, RemOil, or Birchwood Casey Sheath, I prefer the latter because not only does it work, but once again it smells really good in a gun kind of way

) and wipe down all of the metal parts. If you are going to store the gun, run a patch soaked with preservative through the barrel followed by 1 clean patch.
For putting up targets, the nest month or so will be a good time to get some target holders. Those political signs in peoples yards make good target stands to put tape targets to. Don't steal them from people, just ask them if you can have the signs after the election is over.
Ammunition comes with bullets of different weights. lighter bullets recoil less. 30-06 is typically commonly found in 147, 165,168,180 gr loads. stick with 168gr or less. If you sight in and then change your brand of ammo or bullet weight, your point of impact will change, sometimes drastically.
Its perfectly legal to buy ammunition over the internet or from catalog sources such as cabelas as long as you are 18 or over.