If you have been diving a single LP 95 up to now and are just switching to double LP95s, you should be able to self-train. But I would recommend only doing this in an environment in which you are already very familiar / comfortable. If your normal dive location is a quarry, river, etc. do it there and don’t change anything else in your rig until you are comfortable with the change to doubles. If you only do boat dives in open ocean, you may want to try the doubles in a pool first to get the feel, then climb a ladder with the tanks on your back to be sure you can get back in a boat before going out on an actual boat dive. Then proceed to a boat dive you have done several times before in singles.
I made the switch on my own by going from a single LP120 to double LP108s at my local quarry (Dutch Springs) where I had already done many dives. I found the doubles to be much more manageable and stable in the water than the large single, and only slightly tougher to manage on land during shore entry and exit. When I moved to a boat, I found the doubles were about the same as a single for entry, but the extra weight made climbing the ladder a bit harder until I built up my legs a little more. YMMV.