Assess the weight of the font. This is identified by the thickness of the lines that each letter is made from. As sitereference.com states, font weight ranges from the lightest, called "thin," to the heaviest, called "bold." Imagine that you drew a line with a pencil. This would be typically known as a thin font. If you drew the same line with a permanent marker, this would be a bold or heavy font because the nib (width) is thicker.
Compare fonts to help you identify the weighting of the font (and further characteristics). Note differences between thick lines or narrow lines. The most common weight of a font is medium to light, as this is easiest and most attractive to read.
Look at the diameter of the letters and symbols, both individually and collectively, to identify their width. Font width can be compressed or narrow. Conversely, it can be wide or extended. If you put the same word side-by-side in two different fonts, the overall width will be thicker in an "extended" font. On the other hand, a narrow font has a larger height but smaller width.
Identify the font's family of characteristics. Blackletter, sans serif and serif are the three main families. A blackletter font is a traditional lettering that mimics old writing, such as those of gothic or old English texts. Its overall appearance will be classical, as if written with a quill or fountain pen. Use a process of elimination to decide the font's family. This is just as useful as identifying characteristics it does have.
Check whether the font is serif by identifying small brush strokes at the end of each letter. These emphasize the font's shape so that it stands out. A common example of this is the Times New Roman font. You will see that each letter has little protrusions. This is common in newspaper headlines. However, san serif fonts are streamlined and clean. It will not have the small brush strokes on each letter, unlike the serif font. Each character will be simple to look at.