dos parameters and settings

i still use some dos applications, and need to know how can i manage umb
(upper memory blocks), and how do i get the normal conventional memory
"programs and services" to use this area of conventional memory

my need is to free as much as possible conventional ram for the dos program

this is a station that is used in a bussines environment and the application
operated nominaly in xp (any version)

your help will be appreciated

octavio chango