Why should you go there and how do you do it right?

I'd advise against it. This is a royal residence dating back to the reign of King Rama VII, whose name means "Far from Worries," and it remains official royal property. However, it is not open to the public. Upon arriving at the gate on Phet Kasem Road, you will be met by armed soldiers who will inform you that the grounds are closed to the public—a change, according to visitors, that was implemented under the current regime. The stated opening hours, 9 a.m. to 4 p.m. daily, apply to staff and official visitors, not to you.

That's the whole story, and it's important to state it clearly because guidebooks and even tourist websites aren't yet properly informed. That's why so many visitors arrive, are turned away, and leave frustrated. There's no viewpoint, no visitor center, nothing to photograph behind a gate and a wall. Part of the grounds is used for low-cost training and education programs for Thais, which is good in itself, but it's simply not accessible to visitors.