Make a portfolio
First of all, you should make a portfolio in which you will attach your pictures with a detailed resume. You should be original and artistic in your approach. You do not need to make an expensive portfolio rather you should focus on showing your versatility in minimum time. Arranging all the stuff in a file is an old technique, you can impress them by sending a CD of yours along with the resume. This disk will help them to see you in some specific role.
Do some research about the character
Before responding to a call for artists, you should do proper research about the character they are looking for. Make sure that its age appropriate and your personality suits that character. You may read books, browse internet or even watch movies to know more about that role. See if someone has already played that character and try to notice the way it has been portrayed on screen.
Approach via your promoter
If you have signed a contract of talent management company then it is better to approach through your promoter. Though, these promoters charge a significant amount of money as commission but it is the safest way to deal with production companies.
Contact the relevant person
If you are on your own then you should make a call and ask the relevant person about the process. Ask them and then make your portfolio according to their requirements. You should make an appointment before visiting their office. This is to make sure that there is someone to entertain you.
Gather your stuff and walk in
Your next step will be to gather all the stuff and visit the production company’s office. Have a detailed discussion with casting director and submit your portfolio.