In general, science is an attempt to truly understand what’s happening - and specifically so that you can make predictions about what would happen if you did something new that you’d never done before.
The scientific method is the general process for accomplishing that, that our species has developed over the millenia.
Science and the scientific method are, in essence, the same if you think that there’s only the one method. If there’s multiple methods - and we have simply failed to glom on to some alternate methodology - then science and “the scientific method” are different things. …But let’s assume that the method really is just the one and true way.
Then, the closer that you get to the method, the more it is “science” and the further you are from the method, the less it is “science”.
Since the goal of science, as said, is to try and understand things at a level where it lets you make useful predictions, any testing that you do (e.g. mixing and measuring) should be with an eye towards teasing out details that hint towards a particular explanation of the underlying nature of the elements that you’re dealing with. The more that you take a structured approach to devising combinations of mixing and measuring, the more you’re doing science. Ideally, you’re creating testing tables, and populating them with results. You would sit down and think about what “mixing” really means. Does it mean ratios? Does it mean methods of mix? Might the results of mixing change depending on the external environment (temperature, altitude, lighting, etc.)?
To some extent, you might be able to do all of this and keep track of it in your head. Writing it down, though, is usually necessary - even for the average genius. So while I’d be skeptical that someone is doing science, when they’re not writing stuff down, that’s not a perfect metric.
Doubting yourself and your conclusions has generally been shown to be a very useful component of the method. Being able to walk others through your steps, ideas, and results - and actually doing that - are all strong indicators of a devotion to science. Making sure that they can do the same thing, and that they can’t come up with better explanations and better predictions than you, would both add to that.
Science isn’t binary. More sciencey is more sciencey. Less is less. You’d have to know everything a person is doing - including inside their head - to be able to properly rate it. The simple phrase, “measuring and mixing” is to vague to be able to give a meaningful score. Could be a 0. Could be a 3.5. It’s probably not a 10.
ETA: And looking at the linked thread, I’d note that for most of human history, advancement in capabilities appears to have come more from luck than from gaining an innate understanding of things. Most people for most mixes and measures are at a zero if they haven’t been exposed to and trained in the scientific method.