This was something I did with my big purple Adventure Kid's Bible, it seemed like the kind of thing that needed colorful tabs.
I think I was probably watching True Detective or something while I did this, I remember the TV being on. Just using regular graph paper I laid out a grid of colored squares with abbreviations of bible book titles on them. I had checked and knew they would be the right size to fit from the edge of the page to the edge of the cover. Some bibles give you a lot of cover, some don't.
I then cut these into strips, then snipped each tab off individually as I was ready to use it.
On the far left here you can see how these were attached, simply with transparent tape. I made these to be specifically the width of scotch tape, which is exactly three quarters of an inch. Basically you adhere your tape to the bottom side of the page first, then, with a flap of tape sticky side up sticking out, you lay your tab on top, butting it right up to the edge of the page. You then fold the tape flap over, adhering it to the top of the tab and the page, rubbing any air bubbles out carefully.
You start out with Revelation or the Concordance/Index, whichever's at the end of your bible. In this way, you will then be able to tell where to place your next tab for the book of Jude, directly to the left of the one before it. You then proceed in like fashion until your bible is finished.
Took awhile, but it was worth it!