I think the key here is a healthy dose of confidence, but even if you feel you could strut into the workplace looking like a Clinique Chubby Stick, this may be a bit too daring for a more conservative office...
I've always loved bright colours in the warmer season, but for me it's about moderation and mixing with less "in your face" hues. So, rather than going all out with an orange dress, electric blue pumps and a pink handbag, I try to pair the same orange dress with light taupe sandals and a neutral tote. Another alternative is to brighten up an otherwise boring ensemble with bright accessories, like my fuschia YSL slingbacks or a silk scarf. As much as I love clashing primary colours, I'm not sure it works in the office... On the question of mixing, I know colour blocking is pretty big, but best limit yourself to two bright hues, maximum, at least for those days when your calendar is filed with board meetings!
If like me, you like brights, one way to work it is to stick to classic shapes, avoiding frills and ruffles... Otherwise people might ask if you're coming straight from a party or going to one. You want to look stylish and office appropriate, not totally overdressed! Think a purple A-line shift, a royal blue shirt, or a yellow straight tote.
Finally, remember to pack in a good serving of attitude, because bright colours will automatically draw people's looks, so make sure you own the look!