Advice needed - Sinar reflex magnification

Hi everyone - I'm seeking for advice for how I can maintain focusing reliability when using the Sinar 4x5 reflex. I'm starting to shoot some fashion using my Sinar P 4x5 and wanting to know if there's any recommendations for ensuring, whilst using the 4x5 reflex, for what can be done to ensure consistent focus. Would it simply just be a matter of setting at f45 or f64 as to fill in as much hyperfocal as possible? (much the same way I understand Avedon and Nick Knight practiced for their fashion shooting when they used 10x8?). Of course the talent will be on their mark (barely any deviation in subject distance, etc shot to shot as they'll remain static). I have plenty of power in my flash floor packs so achieving the small apertures will be no issue.

I'm only new to using the 4x5 reflex as I've only ever used a dark cloth and loupe for still life subjects all these years, though wanting to rely on something faster yet still reasonably precise for this more dynamic type of photography.

Thanks and have a great day!!

Any suggestions?

You maintain focus by not moving anything and...focusing. The Sinar reflex viewer is no faster or more precise than a dark cloth and loupe, it just makes the image right-way up. In fact, it's probably a bit less precise, because you've only got relatively low power magnification built in, rather than going at the GG with, say, an 8x loupe. Treat it like a dark cloth you don't have to hold and wrangle. Then, you've still got film to load, slides to pull and replace, etc...

Ain't nothing fast about large format.