Download the source ( https://d396qusza40orc.cloudfront.net/getdata%2Fprojectfiles%2FUCI%20HAR%20Dataset.zip )
Unzip the source ( https://d396qusza40orc.cloudfront.net/getdata%2Fprojectfiles%2FUCI%20HAR%20Dataset.zip ) into your local folder, creating the directory "UCI HAR Dataset"
Put run_analysis.R into "UCI HAR Dataset"
Open R or RStudio
Change the current dir to your local folder\UCI HAR Dataset
Run source("run_analysis.R"), which reads the dataset and write the file tidy.txt, a 180x68 data frame.
Use data <- read.table("tidy.txt") to read the created file, which is a 180x68 data frame, because there are 30 subjects and 6 activities.