From Tokyo(Tokyo Station) :
[Rail] Take JR Tokaido Shinkansen Line for 2 hours and 30 minutes from Tokyo Station to Shin-Osaka Station. Take a subway for 15 minutes from Shin-Osaka Station to Namba Station.
From Osaka(Namba Station) :
[Walk] A five-minute walk from Namba Station to the Dotonbori area.