Since January 2017, the restriktor package is available on CRAN. Therefore, to install restriktor, start up R and type:
install.packages("restriktor", dependencies = TRUE)
You can check if the installation was successful by typing
library(restriktor)
When the package is loaded, a startup message will be displayed showing the version number, and a reminder that this is beta software:
This is restriktor 0.4-60
restriktor is BETA software! Please report any bugs.
If you see this message, you are ready to start.