Siem Reap to Shanghai to Beijing to Osaka to Bangkok ( home)

I'll travel from Siem Reap to Shanghai to Beijing to Osaka. I'll have 5 hours stop over in Shanghai and I would like to check out the Maglev train and come back to the airport. I have no visa for China and I'm a Canadian passport holder living currently in Bangkok. Then, I'll spend 1 day in Beijing and fly to Osaka the next day. What should I do to be able to ride the Malev train in Shanghai?