I also felt very strongly that it was okay if I didn't know all the answers. Indeed that it was a better educational experience because I didn't know everything: my ignorance put more pressure on the students to find out for themselves. But I surely wouldn't have had as much confidence in that theory when I was starting out as a graduate student teaching lab sections when I was only a few of years older that the average UG student in class. And if I was a young woman, or a young black woman, or trans, how much harder would it be to be wrong or to not know the answer? That being said, it's also really important to convey a Joy of Science enthusiasm for the tasks to be covered; even if those tasks were intrinsically not-the-cutting-edge "discoveries" of, say, Hooke's [1676!] Law about strain, stress and springs.
The pressure to assimilate about dress, comportment and being your true self by 'Trai Spikes [R about to get all wet in the field], a black student running ecology labs in Oklahoma U. Along the way growing up, he'd bought into Polonius' advice about apparel oft proclaims the man: that you get more respeck if you dress up. You'd better be stonking bri'nt if you turn up for a job interview in a tee-shirt and trainers; while an ironed shirt and pressed trousers will show who's in charge of the Biology 101 labs. But then young Trai was brought to realise that he was being viewed as a sell-out to The Man by his minority students. And he found that being his true self made him happier in his own skin and that allowed his passion for science to radiate around the room and inspire another generation of young scientists.
I have a nice little story about looking the part from when I was a post-doc in TCD in the early '90s of the last century. In the Genetics Department we had a weekly seminar series and a small budget to bring in visiting speakers. My boss, who had done his PhD in Edinburgh, decided to invite Howy Jacobs from Glasgow to do us the honour. Coincidentally the department had recently advertised for a New Professor of Genetics. It was a bit late in the century for punk, but Howy appeared with tartan trews and a mohican [still has] . . . which he'd dyed kelly green to mark his visit to Dublin. My Boss, as you do, took the visiting speaker to the Senior Common Room for lunch. As they sat around having coffee in the deep arm chairs afterwards, a couple of tweed-jacket-leather-elbows academics approached. One of them arched an eyebrow to indicate irony and said
"Ah Paul, is this one of the candidates for the Chair in Genetics? Won't you introduce us?"
"No, this is Howard Jacobs, the Lister Professor of Microbiology, at Glasgow, he doesn't need another chair"
<pffffffff> collapse of stout party!