Windows users: after starting R, the package is simply installed using the menu option Packages -> Install Package(s) from CRAN and then select shapes from the long list of packages.
Other platforms: see below and the R web pages.
A quick tutorial (text file) is available.
Brief installation instructions: INSTALL
Dryden, I. L. (2012). shapes package. R Foundation for Statistical Computing, Vienna, Austria. Contributed package. URL http://www.R-project.org
@Manual{Dryden12,
title = {{\tt shapes} package},
author = {Dryden, I. L.},
organization = {R Foundation for Statistical Computing},
address = {Vienna, Austria},
year = 2012,
note = {Contributed package},
url = {http://www.R-project.org}
}