The Göttingen Septuagint is the premier critical-scholarly edition of the Septuagint. If you’ve ever seen or used it, you know it can be intimidating. Fortunately, Abram K-J (Words on the Word blog) has created a primer in two parts on how to read and understand the Göttingen Septuagint. Here are the links (highly recommended):
How to Read and Understand the Göttingen Septuagint: A Short Primer, part 1
How to Read and Understand the Göttingen Septuagint: A Short Primer, part 2 (the apparatus)
And it goes without saying you should have the digital version of the Göttingen Septuagint.
Some of us are making do with Rahlfs until our ship comes in. Gottingen= big bucks in any language
yep; it’s pricey, but for those who want text-critical info for the LXX, indispensible.