On the right hand side (unless using a mobile) there are some links you can copy to place in a post, e.g. Share BB [GALLERY] Code:
Code:
[GALLERY=media, 96097]TRV4-3-50 by D_Hailsham posted 26 Sep 2015 at 4:49 PM[/GALLERY]
.
But easier than that if you click on the icons of the camera on the toolbar above the post box it brings up your images (similar to the 'old' forum) and you can click on the required one and it inserts it.