step-by-step manual titled How to Build Ramps for Home Accessibility is available from the Metropolitan Center for Independent Living (MCIL) in St. Paul, Minnesota.
Your ramp project may need a permit from your town.
Take a copy of your plans to the officials
Be certain to tell them if the ramp is temporary so you get the correct permit.
Advice can be obtained from your rehabilitation commission:
help is available from http://www.ramps.org/contact-us.php
Information regarding ramps; https://www.google.com/search?q=access+ramps+for+the+elderly