An effective way to ensure you are able to come across as someone who has good taste is to keep up-to-date. Read good quality magazines that are considered tasteful, visit stores that sell stylish, of-the-moment clothes and accessories. That way, as if by osmosis, you'll become both familiar and au fait with what for some of you may be very new.
In the 21st Century we can live such busy lives that it's very easy to lose awareness of the ability we all have to control our emotions, our state of mind and the skill of planning for happiness. Rather than just letting life happen to you, how much better might it be to consciously steer it, through your actions, thought and feelings, in a more positive direction?