A few things I didn't understand in my first year of photography

Depth of field:
Your camera's ability to stop down the lens while still allowing you to see through the viewfinder is an important feature. With this depth of field preview, you can tell what will be in clear focus when the shutter is released. If you are using a small aperture (f/16) you can also see the "hot spots" in the image. This may help you judge if there is too much contrast in the scene for the film to handle.

Tripods are a necessity. The bigger and the heavier the more stable. Unfortunately, they are also more difficult to carry. Nevertheless, the more stable the tripod, the sharper the image. A good tripod head is also a necessity. Hand held shots are generally throw aways unless you are using image stabilized lenses.

Quality of light:
Look for good light then look for something to take a picture of. The quality of the light near dawn and sunset is generally the best. It has a warm (red, yellow, orange, cherry) quality that enhances most subjects. During the day, most of the light has a blue cast to it because the sky serves like a large blue umbrella which reflects blue light on everything. This is especially true for objects in the shade on a sunny day. Most of the light in the shade is blue light reflected by the sky. Scout things out during the day. Shoot near sunrise and sunset.

Teleconverters do cost you a stop or two of light but they do not increase the depth of field at all. So if you have a 2X teleconverter and the camera says it's f/8, from the depth of field is the same as your lense at f/4 without the teleconverter.

Setting Exposures:
Camera meters are set by their manufactures to "assume" that the light coming through the lens (TTL) is on average 18% of the light hitting the subject. The reason that they calibrate meters this way is that 60% of things on the planet reflect close to 18% (middle toned) of the light that hits them. Therefore auto exposure works correctly for about 60% of the objects in the world. Unfortunately, the light toned and dark toned subjects won't be exposed correctly if you leave it up to the camera. The camera will try to turn everything to middle tone. It will under expose light toned subjects because the camera thinks it's seeing 18% of the reflected light but for white objects the camera may really be seeing 90%. Since the camera assumes the 90% reflectance is 18% it thinks that it can choose a shorter shutter speed and get properly exposed image. The shorter shutter speed will result in less light reaching the film and that will result in turning the white object to gray. Therefore, if you use the camera's meter you must compensate for the meter's unbending assumptions. Following our example of exposing for a light toned object, since the camera will select a faster shutter speed than what is really needed you must compensate by adding more light. This can be done by lengthening the shutter speed or by opening up the aperture. Generally for snow to come out white instead of gray, you have to over expose from the meter's suggested exposure by 2 stops.

More Things I Didn't Know:
I thought that what you saw through the viewfinder was what your picture was going to look like. Most SLR's are not WYSIWYG (what you see is what you get). The majority of SLR's show less than 95% of what the final image will encompass. Because of this I was getting a lot of images with distractions at the edges of the frame. If you own a camera that shows less than 100% of the final image, besides checking the edges, you need to move the camera around to make sure there are no distracting items just outside the edges of the viewfinder.

You can check your camera's meter by pointing it due north about 45 degrees from the horizon at midday. At f/16 the suggested meter reading should be the speed of the film loaded in the camera at the time of the test. It's probably not a bad idea to check the metering once in a while. You can also check it with an inexpensive gray card (available at most camera stores)

Regarding composition, I find one of the best ways to find a pleasing composition is to approach the subject hand holding the camera and when you find a pleasing composition, set up the tripod so that the camera is back in the position where you found the pleasing composition.

"Pushing" film means setting a higher ISO than the manufacture's suggested film speed. For example you might over ride the ISO setting on Velvia (ISO 50) and set the film speed to 100. Since all the images will be one stop under exposed when you send the film in for processing you instruct the lab to push the developing by one stop. If the lab follows you instructions, your images should come back properly developed for ISO 100. Essentially, you can increase the film speed of your film by under exposing then push processing. You might consider this if you are shooting in low light and you subject won't hold still.