Larry, you can do it!
First, make sure you put a "crumb layer" of frosting all over each tier (if you are doing more than one). This is just a layer of frosting which will help the fondant stick. Refrigerate the cakes until this frosting layer is hard. This helps because the soft frosting acts like glue, but you want to get it all in place and smooth first. Does that make sense?
Measure the height and width/diameter of your cake, multiply the height by 2 and add it to the width. This is how much fondant you will need.
Put a light coating of icing sugar or cornstarch (my choice) on the surface you will be rolling on. Knead the fondant until smooth and pliable. Roll it to the desired size (a little bigger is good) and 1/8" thick. Loosely roll the piece of fondant around the rolling pin and take it to the cake. Try to position it so there is at least enough fondant to cover the cake to the edge of the board - extra is desired so you can cut it off and get a smooth edge. With your clean and lightly cornstarched hands, or a fondant smoother, gently pull the fondant and smooth it to the cake stretching carefully to remove any folds. When it is smooth, cut any excess fondant off the bottom.
If you have any questions PM me or write them here.
"Variety is not just the spice of life, it is the key to life" - Chef Michael Smith