As a hardcore developer and not a graphic designer, I always struggle when interviewing graphic designers/web producers. I know CSS and HTML pretty well theoretically, but couldn't design a single decent-looking page from scratch.
During a face-to-face interview, we can review the candidate's portfolio, but beyond that, what are some good ways/questions to assess the candidate's skill as a graphic designer?
Apart from looking at their portfolio, I would give them a theoretical project and let them explain how they would go about creating a design for it, and give you some initial ideas. A good designer should be able to do this after asking the right questions from you.
The process should give insight into their creativity.
I'd think some questions regarding how well they know about the Web might be useful. For example:
1) Do they know about allowing for those users without broadband a.k.a. high-speed connections?
2) Do they know about compressing pictures or choosing the right type of graphic file, e.g. when is a GIF better than a JPG or a PNG?
3) What kind of animation software are they familiar with, e.g. Flash, Silverlight, etc.?
4) Which web browsers do they use for testing their graphics?
5) Do they design for a specific screen resolution or a minimum resolution?
6) Do they have any examples of a site currently up that they did the work?
Those would be the few areas I'd focus in on besides their portfolio.
You can see how they appraise work from the view of a potential user, rather than just being a web designer. How to design usable websites that don't drive away potential users is a useful skill for a web designer to have - it isn't all about the graphics and fancy CSS.
Also ask them for examples of websites that they like and dislike and why, and then you can assess if their choices would be a good match for your company.
First of all, although you think you don't know good design, if you see enough portfolios, the good ones will probably still stand out to you. If you still don't trust your own judgement, get other people to look over them for you.
Get them to talk you through their work. A good designer should be a good advocate for their work. You can also use the opportunity to assess their technical knowledge. They don't need to know how to program, but they must understand how their work will interface with underlying technologies.
As others have already said here, another essential is to be able to appraise their work from a usability perspective, not merely an aesthetic one.
Also, I wouldn't take on a designer who doesn't understand at least the rudiments of xhtml/css, unless you're willing to teach them.
Finally - an alternative to setting tests is to take someone on a freelance basis to begin with, and find out for real how well they can work with you.
Just do me a favor. Don't ask them to create a three column table-less page on a whiteboard, and get upset when they don't write down the doctype.
So they're not just web designers, they're front end developers?
I'd ask them to talk about:
Ask him or her about teamwork and conflict and all the things that are important to know about someone who you're going to have to be working with.
I have also gone through same situation: Though conversation is really important to assess the candidates mind, but I feel graphic designer can be truly assessed best, practically. 1. Show him/her some page of ur or some other website. Ask opinion, and listen to feedback. 2. Give him a comp and photoshop an ask to design something for you. Maybe redesign an already existing web page or throw him a concept and see what he comes up with roughly.