One of the rights you retain as an author of material published by ACM is the ability to make a version of your material available on your own (or your employer’s or institution’s) web site.
The ACM article template offers the ability to prepare an “author version” of an article or abstract, which includes an appropriate rights statement on the first page which points to the version of record in the ACM Digital Library.
One can also use ACM’s Author-izer service to obtain and use a link which points to the version of record in the ACM Digital Library.
The use of the Author-izer service is beneficial in several ways: it relieves you of the burden of creating a separate “author version” of your published work, and drives traffic to the version of record in the ACM Digital Library.
More information on the Author-izer program is available at http://www.acm.org/publications/authors/acm-author-izer-service.