How to Install multiple theme in wordpress

already i was install theme(‘martin theme’) in wordpress in my site.
is it possible to install one more theme in same wordpress?

Note :
purpose to use multiple theme for different layout,header & Footer for post page.

actually i was tested to create multiple header & footer, its working well in page only. but i want to use in post page. can any one suggest me,how to create different layout for page & post page in wordpress.

i tried to create sub-domain to use to multiple theme, but i have only one database, so its failed to install that.

Thanks