How to send goods in exhibition between a state(intrastate)

Where the goods are supplied to a trade exhibition in an another State where the supplier of the goods does not hold any office premises, he would be required to obtain a separate GST registration as a casual taxable person and would also require making an advance deposit of the expected GST which would be payable. However, in the case where the supplier simply transported the goods for exhibition purposes only, and not for the purpose of supply, the said goods may be taken to the trade exhibition under a delivery challan. At present, no documents under GST law have been prescribed.  Therefore, the Supplier of the Goods will not be required to obtain a separate registration as a casual taxable person under GST law if no supply of the goods is made in that state.

In other words, where a person (who is already registered under his state GST) participating in a trade exhibition in some another state only for one event need not apply for GST registration separately. Though, he has to take the GST registration in another state (in the state where the exhibition is being held) if he supplies goods from that state.  

For an example, If a company in Rajasthan participate in a trade exhibition event in Chennai, will be required to obtain separate registration in Chennai only if the company provides any supply from Chennai.

but what if after exhibition in chennai goods sent to bangalore for another exhibition and then to mumbai for another exhibition. after that now 2 scenario

1) sold goods from Mumbai exhibition

2) come back goods to chennai and then sold from chennai

in both cases what procedure needs to be followed in GST?