I found an article that looks at the 8 Essential Elements to a Comprehensive Brand Identity. I found this to be fairly helpful when looking at making my own logo and brand identity for High Seas Ink. Below are the 8 points that they made.
1. Logo or wordmark A logo is the graphic symbol, whereas a wordmark or logotype is just the name of the company set out in a particular, fixed way
2. Different logo “lockups” Although the logo needs to look consistent, it should have variations based on placement and fit
3. Key colours Key colours are used to define the company. Often two are used but some can more complex
4. Additional colour palette options Other colours can be used, that complement the original logo, which bring the brand identity together
5. Corporate typefaces Only a few fonts should be used in one brand identity and should be available on a computer
6. Standard typographic treatments The way things are written or laid out should be similar across platforms
7. Consistent style for images All imagery should have a consistent look and feel
8. Full library of graphic elements For example background textures, line style treatment or use of white space