In terms of how? I simply silicone the sides and bottom to the glass, fill in behind it with coco fiber and done. Plus, then its kinda like a planter. Id just put peices up and fill inbetweeen with coco fiber
I think the cork bark back ground your looking for (reading your other post) is a pressed coconut fibre panel. its 1/4-3/8 thick, you silicone it to the back of your tank and use the pins talked about in your other post to mount plants. most pet stores, or suppliers on this sight sell them
the other type of coco-back ground is made using sylicone, smeared over the glass (use the brown colored sylicone so it doesnt show as much) and then cover it with coco fibre bedding. this is a much thinner layer and im not sure if you can mount to it or not.
The cork style back ground, you can get either cork bark tubes or flattened pieces of cork bark. again, sylicone it to the back of your tank, and if there is a gap (as they are not perfectly flat) back fill it with great stuff so the frogs cant get in. depending on the size of your tank, you could go with a couple flattened pieces with the coco fibre/sylicone in between.