You can watch Regular Show through several streaming platforms:

• Hulu offers Regular Show for streaming as part of its service.
• YouTube TV also has the show available with a free trial option.
• HBO Max streams Regular Show, although availability may vary by country.
• Netflix has Regular Show available for streaming.
• Amazon Prime Video has the show available to watch as well.

Additionally, some episodes or seasons can be found on the official Cartoon Network YouTube channel, which uploads compilations and episodes. So, the main popular platforms for watching Regular Show are Hulu, YouTube TV, HBO Max, Netflix, and Amazon Prime Video.