I grew up hunting without the advantage of a scope on my deer rifle. My Grandfather taught me to hunt using iron sights and when I had mastered shooting, he bought me my first scope. I used a 30-30 Marlin and he had to get the rifle drilled and tapped so that a scope could be mounted on to it. He took my rifle to a gunsmith to have the scope put on, but if your gun is already set up for a scope mount, attaching a scope is a breeze.
You obviously need a rifle to attach a scope to, so you need to purchase a rifle to get started. Some rifles can be purchased with a scope already mounted, but if not, you will have to pick out a scope that fits your hunting needs. Choosing a riflescope depends on how much money you want to spend and according to distances in which you will be shooting. Most riflescopes come with mounting equipment to attach the scope to your rifle. If the scope doesn't include these items, you will have to purchase them separately.
There are several different mounting kits you can buy for your scope. You can purchase see-through mounts, side-mounts, and regular dovetail scope ring mounts. See-through mounts are good if you want to be able to use your scope and transition to iron sights if you need to use them. Side mounts allow you utilize your iron sights as well. Dovetail mounts inhibit you from using your iron sights, but these mounts have to be purchased if your rifle only has dovetail receivers for a scope mount.
If your rifle receiver is already drilled and tapped for scope mounts, you can attach any scope mount with Allen-wrench screws. Dovetail mounts can only be placed on rifles with dovetailed receivers. Once the scope mount has been placed on the rifle, it's time to attach the scope. The first part of the scope mount screws directly to the rifle's receiver. The scope is then placed in the grooves of the scope mount. Place the scope in the grooves so that the scope is at least 3-4 inches from your eye when holding the rifle in a shooting position. This distance will keep the riflescope from hitting you in the face after rifle recoil. Place the top rings on top of the scope and clamp them with Allen-wrench screws to the bottom scope ring mounts. Do not over-tighten the screws or they might damage the inner workings of your scope. Most scopes are for right-handed shooters and the wind-age and elevation knobs should be set up so that one knob is on top of the scope and one is parallel to the ground on the right hand side of your rifle.
Look through your scope to ensure that the cross hairs are line up perfectly. If they are not, loosen the top rings of the scope slightly and turn the scope to make the adjustment. After all adjustments are made, re-tighten the scope rings and your rifle is ready for the range.