I pretty much always use low strength mix maybe 2%, spray on with a backpack and a single gardiner spray tip, leave to dwell, then a light scrub off.
Sounds like you’re doing it well!
And yes, all my clothes are ruined. Primark t-shirt replacements regularly
although to be fair, when doing SFG cleans, it’s less messy, and more controlled with a slower application, so less mess.
You can now buy a single spray tip adapter from gardiners, but I’ve had the old red fan jet setup for years, pushed straight into the 5mm pole hose which I’ve cable tied in position on a bare quick lock angle adaptor. It’s perfect for controlled spraying of gutters/facias.
Often I actually use the fan jet with normal water after the hypo has sat for 15 mins to ‘blast off’ the dirt. Means no scrubbing at all. This is obviously dependent on how dirty they are.
I hate scrubbing gutters