If you're working on your 10 Steps to Becoming a TV Expert (read them here), at some point you'll be booked for a screentest (read tips here) or a straightforward, on-the-couch interview.
If it's the latter, the first thing you need to do is prepare - ie is the interview live or pre-recorded; how long is it; what's the angle; what's the 'tone' of the show; who are the viewers; what are the key messages you want to get across; what examples are you going to use to bring the interview to life and get your messages across in a way that's succinct & relevant to the viewers; etc.
Having done your preparation, the next question is: what to wear - and what not to wear? And here are some tips:
1. Do some research. If the show is a live, daily show, watch it and look at what the presenters and guests are wearing. Is it formal or informal? Smart or smart/casual? What looks good and what doesn't. What colours clash with the set, etc?
2. Avoid checks, stripes and small patterns because they strobe.
3. Avoid black (very few people look good in it).
4. Wear block colours.
5. If you're filming in a studio, wear fabrics that don't make you sweat (it gets VERY hot under studio lights).
6. Remember that a microphone will be attached to your top - and that the battery pack and wire will be fed down your back and attached to your trousers, skirt waist, etc. So good necklines and easy access clothes are important.
7. Because of the above, steer clear of polo necks.
8. Avoid jewellery that will rustle up against the microphone that's attached to the neckline of the top you're wearing. You don't want your interview to be cut short because the sound is awful.
9. Wear clothes/necklines that flatter your shape.
10. Cameras really do add pounds so avoid thick, bulky fabrics.
And to complete the 'look', sit up straight, relax your shoulders and smile!