How to properly expose my camera?

Ok so I'm a hobby enthusiast photographer. I currently am set up with a basic d5100 nikon camera with a variety of lenses from a 35mm prime to a 300mm zoom. I'm pretty familiar with its features but I have one type of shot I'm struggling with. If I have a subject with the sun behind them how can I properly expose the picture. I've seen photos taken where the sun looks nice and reasonably clear and yet the subject is well lit and the foreground looks great. Like for a senior picture. I either get the sky properly exposed and the subject is in the dark or the subject looks great and the sky is way over exposed. So how do I get the perfect blend. I have in camera HDR but even that doesn't cut it. Is it basically post photo shoot editing? Photoshop with overlay? Or is it later in the day and the subject is lit with speed lights to help keep everything bright? It's a shot people pull off I can't seem to get. I tried to get a horse in a shot. The grass was golden and lit by the sun. The horse looked great. But when I took the shot the sky was white and over exposed. So I readjusted and got the sky but the horse was in the dark. Thanks for any help. I shoot in RAW format on manual settings.

If the subject is backlit, you have to add light to the subject to balance the exposure. Often some fill flash, or reflectors or both. You can combine pictures in post processing as well, much easier to do it in camera.

Fill light. You expose for the background and fill in your subject with a flash.

Here are a whole bunch of examples of what they are talking about.

Look at the "before and after" (with and without) of the two girls.