First impressions can be a challenge in this industry whether it’s your game or yourself. Making sure that someone understands your personality is half of it, and the other half is seeming intelligent. I say “seeming” because it’s only an impression and whether you’re actually intelligent or not is what determines you keeping that connection, not getting it in the first place. That’s also the category that professionalism falls under.
People often under-estimate professionalism in the industry, as far as I’ve noticed. You don’t put references on a resume, and “dress for the job” in the game industry is… shorts and a t-shirt? When walking around Electronic Arts you notice that some of the hardest working professionals in the industry are wearing shorts and sandals – a reason I love this industry.
Professionalism in the industry isn’t based on appearance or a first impression, it’s based on a lasting appeal and production quality. In other words, the industry professionals are representations of the games they make.
You can make the best first impression possible (like a cgi trailer) but turn out to be a total snuff (Brink, anyone?) You can come off as a brilliant systems designer with great ideas, but maybe those systems just don’t work or aren’t fun. Some things are just better on paper, or as a first impression.
Professionalism for people in the games industry can be directly correlated to their production methods for game design, and that’s the way it should be.
Of course making a good first impression is important to getting that job, but if you’re bad at that and you’re a good designer just make sure your work speaks for itself, and you.