I’ve recently given a workshop at Donuts and Distribution, a statistics reading group for the Second Language Studies program at Michigan State University, on the topic of visualizing data. The presentation slides and workshop materials can be found on my RPubs page, Part 1 and Part 2. These were designed for novice/intermediate audience.
Part 1 has a more step-by-step approach for beginners and includes boxplots for comparing groups, scatter plots for correlation, and parallel coordinate plot for repeated measures.
Part 2 includes graphics for showing interaction, repeated measures with more time points, and barplots for survey data.
Some of the data sets I used are what’s available from the companion website for Larson-Hall’s (2015) A guide to doing statistics in second language research using SPSS and R.