Fatal Error Help

I tried to install the Membership Plugin on my website TheLandofColor.com. Got this error message:

Fatal error: Allowed memory size of 67108864 bytes exhausted (tried to allocate 30720 bytes) in /home/lori/public_html/TheLandofColor.com/wp-admin/includes/media.php on line 949

Had to go into the files thru my host and delete the Membership Folder files to make the error message go away.

But I would like to use the Membership plugin -- any ideas how to fix this?

Thanks.