Below is a collection of guides and tip-sheets for applied micro RAs. I take credit for none of them, they're the work of many others dedicated to helping RAs. I'm collecting them here so they're in one place.
General Tips
Stata
Data visualization
Advice on resources for R from Brandon de la Cuesta:
I think swirl (https://github.com/swirldev/swirl_courses#swirl-courses) is quite good cause its in the R environment (interact directly in R studio or whatever ide they choose) and there are a host of courses they can choose from
one of which is the getting and cleaning data course which covers dplyr, tidyr, lubridate, etc (https://swirlstats.com/scn/getclean.html)
the R programming one i think is probably a reasonable place to start off or this very short intro to R one (https://swirlstats.com/scn/A_(very)_short_introduction_to_R.html)
for spatial data resources i think these have been mentioned before but this using spatial data with R is a good short intro (https://cengel.github.io/R-spatial/) and geocomputation with R (https://geocompr.robinlovelace.net/spatial-class.html) is a good long treatment of spatial data