Depth of field is made up of different factors. On your camera you have to adjust your apeture the larger your f-stop is, the better your depth of field would be in that photo. If your f-stop is a smaller number then your photo would have a shallow depth of field. Along with that, your camera mode should be on apeture priority because apeture affects the depth of a photo. Another factor that affects the depth of one of your photos is the distance you are away from the subject. If you are far away and zoomed in your depth of feild will be much more shallow than if you were close to the subjects and not zoomed in.

If your apeture is a low f-stop like if it was F/5.6 and your are far away from the subject and you zoom in, then your phoot is bound to have a shallow depth of field. But if you are close to your subject and you have your camera on a larger f-stop like F/16 then your photo will most likely have good depth of field. Another thing that factors into depth of feild is focusing. You should have your camera on manuel focus to really capture the effect you are going for. Another thing you can do to work on your depth of field skills is analyze depth of field in some photos your like so you can really absorb the photo. Knowing what good and shallow depths of feilds are will help you create your own photos with depth of field.