Xplet1veDeleted 's embedded within the owner profile?
Currently, limitation is one PS per profile
Xplet1veDeleted And accessible just by a tap?
No. It's locked by default, you can choose unlock method - there are several options. See settings
Xplet1veDeleted And whatever's in there still can't get access to any of the rest of the phone, the PS still serves as an effective sandbox?
In general - yes, though there may be some peculiarities (can't recall I saw smth significant for me). For example, you can enable shared clipboard between host profile and PS if you want. It's a bit easier to transfer files between it and host profile, but that's not worsening separation, from what I recall, it's just a side benefit they're running (dunno how it's called) at the same UI
Xplet1veDeleted So do I have that right? Is that how it works?
No. Please read above.
Xplet1veDeleted How do you set it up
Search settings for it, it should be straightforward with default settings.