As you are just entering the "Lettering" phase of your career, get off to a good start. Begin by "investing" in a good font collection. Avoid most of the self installed Microsoft fonts you most likely have on your computer, as they are the same worn out, over used fonts every other numbskull illiterate computer operator is using. Instead, set yourself apart from the crowd, (your competition) by using fonts from these three major font providers. SignFonts.com, SignDNA.com and Letterheadfonts.com. You won't be disappointed with any of these in your collection.
Also, get yourself a subscription to SignCraft magazine and study every portfolio piece you see in it. I doubt you will recognize very many of the fonts used by these artist. They understand the importance of using an appropriate font on each and every sign they design.
Fonts can make or break a sign depending on the ones you choose to use. Fonts have personalities and can really help express the meaning and message of any sign. Some are utilitarian, some are decorative, some are formal and some are casual. Learn which ones to use.
Mike Stevens book has some great examples of fonts used well. Keep studying everything you can find on typography. It's a very specific and important part of sign design just as proper use of color is. A sign is many more parts than just sticking a letter on a board. A great sign is the sum of many important design elements!
Have fun with it. If you're balls are big enough, post up your designs for some honest critique before you sell a job, not after. You will see your portfolio grow very fast with good designs...
That's my .02 worth!
