You could create an arrangement for any size vase, the larger the vase, the more flowers and greens to use. For Christmas time, use red, white and maybe even green flowers (like green button mums). Also choose from a variety of greens and evergreens out there. Accent a red rose in a bud vase with some baby's breath and cedar. Deep red alstroemeria are especially beautiful. There are many other flowers that would be perfect to use for Christmas arrangements, the link below will take you to a complete list of flowers, foliage, and evergreens for Christmas floral design.
Choose a container that will complement the shape and color scheme you have in mind. If you are just starting out, go with a traditional size vase __ not too tall, and not to squat. As a general rule, your container should be about one_third to one_half the size of your finished arrangement. So, for a vased bouquet you'll need mostly flowers with longer stems. A smaller bowl or basket is fine, too. You'll simply have to cut stems shorter and may need floral foam to help position each bloom. It helps to start with the simpler designs and work your way up, and a vased bouquet is often recommended for a first project.