A resume is what you staple onto the back of your headshot when you submit your headshot to agents and casting directors. 
A resume consists of contact information about yourself, your experiences in acting, training, and special skills.
Whenever you send out a headshot, you should staple a copy of your resume to the back of the photo.
A resume is broken down into three parts; Contact Information, Experience & Training. 

CONTACT INFORMATION

The contact information is the single most important part of a resume. Without it or if it's incorrect nobody can
contact you.  Make sure to double check when making a resume that you have the correct information. 

NAME:

At the top of your resume should be your name. Your name should be in large bold letters to make it stand out
from the other information. The top of your resume is the first thing an agent will see when they look at it & you
want them to remember your name so make sure it's large & bold. Just don't get carried away.  On the side of
your name you can put your union affiliations if any. Some people apply the union logos to signify union status.
It is perfectly fine to do that if you are a member. Some actors put their age on the top of their resume. It's wise
NOT to include this. The reason behind this is because g you want the person viewing your resume to make up
their mind by themselves on how old you look. This can be beneficial to you. If your insistent on putting an age
on your resume supply an age range instead.

PHONE NUMBER

Directly below your name you want to put your phone number. Beeper numbers & cell phone numbers are wise to put on also. If you have an email address you can supply that also. You don't have to put every phone number you have, again don't get carried away.

EXPERIENCE

Next comes your experience section.  Most resumes are broken down into three sections, theater, film, and television. 
The area that you are looking to further your career in should be placed on the top. For example, if you want to do television,
 the television section of your resume should be on top right below your contact information.   Each section of your resume
is than broken down into three parts, production title, role & production company.

TRAINING

After your experience section comes the training section.  This is important because it shows the agents and casting directors
what parts of acting you have studied specifically.  This also shows them that you are continuing to educate yourself & better
yourself as an actor. The training section has the same format as the experience section. It is broken down into three parts:

Training Class Title
Topic Studied
Instructor

SPECIAL SKILLS

The last part of a resume is the special skills section.  This part includes special skills that you you are proficient in.
For example, a movie is being filmed & they need someone who can firewalk. If the director sees on your resume
that you can firewalk, you might get the role just because of your special skill.   Do
not put any special skills on your resume that you honestly can't do.  This wastes everybody's time and further diminishes
ever working for that production company again.  You don't want to put down everything that you can do or have done
before.  Just put down the unique or important aspects about yourself that might get you noticed.