Set the winner count and Spinnza draws them one at a time — Winner 1 of 5, Winner 2 of 5 — with each winner leaving the wheel before the next spin. That is the default because it is easier to follow and much better if you are recording it.
Nobody wins twice
Within one session, each entry can only be drawn once. The exception is duplicate rows: if @alex appears three times because of bonus entries, those are three separate entries and can take more than one prize. If that is not what you want, remove duplicates first.
All at once
Under More options there is a “pick all winners at once” switch. It draws every winner in a single spin and lists them. It is faster; it is also less clear to watch, which is why it is not the default.
Backups
If you might need a runner-up, draw them now as part of the same session rather than coming back later. A second draw a week later is a second draw, and it will look like one.
How many to draw depends on how you contact people. A prize claimed through a comment reply on a public post gets claimed most of the time; one that needs somebody to open a DM from an account they do not follow, and then hand over a postal address, does not. If contact is indirect or the prize needs shipping details, draw two or three extra and say in the rules that backups are used in the order drawn if a winner has not replied by a stated date.
When the prizes are not identical
Say which position gets which prize before the first spin — first drawn takes the headline prize, second takes the runner-up, and so on — and then draw. Announcing the order afterwards works exactly as well and looks exactly as bad, because from the outside there is no way to tell it was not decided once the names were known.
The same applies to which prize the backups inherit. A backup replacing the third-place winner should get the third-place prize, and writing that down beforehand takes one line.
If a drawn name turns out to be ineligible
It happens: a staff account, somebody outside the shipping region, an entry that broke a rule. The rule to set in advance is that an ineligible name is skipped and the next name already drawn moves up — which only works if you drew backups in the same session. Without them the only options are a fresh draw, which invites the accusation you were avoiding, or an awkward silence.
Keep the whole session together
Winners, backups and every spin in one sitting, with one entry list. That way the count, the timestamp and the Entry List ID are the same for all of them, and the record you keep covers the whole outcome rather than the first name out.