Step 1:
Let your imagination kick in. You need to come up an idea for your series. Being as it is a series you need an ongoing theme. Probably if you look back at your old sketchings, you will see where you drew perhaps an action figure doing several different things. The theme is what your action figure does. Now you will need to build your theme and once you do this, it becomes your foundation.
Naturally, there are going to have to be various characters in your series. You are going to need to think about each of them and what roll will they play. This does not mean you are designing the plot of the story, it means you are assigning traits to your characters.
Step 3:
Most cartoon animators do not consider themselves adept at script writing. This is where they will rely on an expert in that field. Your job will be to present him with your theme and your ideas regarding that theme. Your scriptwriter is the one who brings your characters to life. He will do this by utilizing the traits you have provided him. Make sure your choice of scriptwriter is one that is well versed in this type of writing.
One of the key factors of your success is making your characters remarkable. You can enlist the services of a good design company for this segment of your project. They almost have to become household names. Hopefully to the point where various products will be designed after them. Imagine a super hero you have erected becoming the hottest action figure on the market. I would class that as the ultimate success.
You are very close to the point of now compiling your character bible. This is where you start to put things into action. This book, which has now become a very valuable commodity of yours, will contain all of the information you have gathered so far from the different venues you hired. You will take your character bible to an animation house in the hopes of having a pilot episode produced.
Step 6:
Now you will have reached a decision-making period. You can approach a distribution company with your pilot to see how marketable the finished version would be.
The other alternative to a distribution company would be to approach the television media to see if there would be any interest by them to produce your show. Here is the step where you have to be confident in your work. You know it is good and now you have to sell others on that very fact.
Step 8:
As you can see, you have a long road ahead of you and there are costs involved. You just have to be determined enough and believe in yourself and your work and go for it.