First, you should create a form using Contact Form 7 plugin, then you can use shortcode to add form into any places you wish.

[contact-form-7 404 "Not Found"]

Pictures

 
1967 Chevelle SS 36 1967 Chevelle 33 1969 Mustang Mach 1 4 Plymouth Roadrunner 22 1968 Plymouth Roadrunner 1960 Buick Convertible 1960 Buick Convertible 1960 Buick Convertible 1960 Buick Convertible 1960 Buick Convertible