Like most creators, my approach to character design is to always start out with a sketch for a road map. The idea behind my character was for a Sci-Fi movie I wanted to make with my kids. It was to teach them how to write, plan, and execute a small budget movie. I needed CG characters for our movie. So, I began creating ideas for our reptilian foe. 

My next task was to begin modeling out the character's basic shape. This was a relatively simple process. 

After the basic shape was created, I needed to begin sculpting the large details. At this point I needed to just get a more detailed shape than the basic model I created before this step. 

Once the general detail is in place, I began to add more finer details. This began to slow my old computer down quite a bit. Sculpting generates a lot of triangular mesh which can start to make things slow. 

Once the fine detail is finished, I needed to retopologize the dense mesh. You cannot animate that much detail without crashing your computer. When you have a less dense mesh, you can begin to texture and paint the character. 

Now here's the fun part. Once I have a low-poly model made for the retopology stage, I can use a shrink wrap modifier in Blender and wrap the low poly model's mesh over the sculpted mesh. This gives me high resolution options without it killing my machine. See in the image below, I can use Blender's multires modifier to adjust how much detail I want to use. 

Here's a fully textured character after I was done. 

Next I began to consider clothes options for my reptile friend. 

...and possible armor and alternate character versions.