See some of my logo designs which I have created for my customers.
A logo design should be usable in a wide variety of mediums and applications. That's why I start to design with hand-drawn simple scribbles.
The next step is to make the idea work in black and white. You should be able to use your logo as a stamp as well as on a promotional pen for example.
Finally I will consider the colour scheme which best represents the emotions that your brand intends to elicit.