Just enable "nesting" on the printer setup and print the images. It is that simple.
Just a few remarks:
1) Every image must get to the printer with the same resolution, otherwise it won´t work. Using tools like "print resolution" option on Lightroom is the best way to do that.
2) It olny nests one row of images at time.
3) If the first image is larger than half of the paper width it will not wait for another image and will start printing right away. If working with different sizes, start with the smaller ones.
4) You should enable crop marks to ease your life.
5) I like to send each image to the printer and pause it. When I have the whole lot paused on the pipeline I just select the ones I want to print and unpause them.
6) Never count with a thight nesting, the width of your images together should be a bit smaller than the paper width (about half inch at least).
Best regards.