For now you can trade them with php in the Tagcash wallet mobile app in a module called Tagtrader.
Or through the exchanges yobit and novaexchange, but then for other crypto only.

I think Tagcoin is also added on the pcm(ProofCoreMoney) blockchain and soon could be traded with other currencies, tokens on the same chain.
As far as I know they are building the Lite wallet as we speak.
You will be issued the same amount of Tagcoin on the pcm chain, once you burn the original ones in the process. 
I am sure Tagbond will give all the instructions when all is lined up 

Great news! I already heard that a new big discount membership platform for tourists and locals in Thailand wants to use the PCM chain for their loyalty points.