Hi Ritu,
although im just a diet expert but let me try helping you with this.. , as the general rule goes , plz avoid wearing prints with horizontal strips, they make you look wider, so try something vertical .. but ya make sure the strips are delicate or use small checks rather then bigger ones .. the delicate prints will make you look sleeker.
try going for colours like black and white , they make you look sleeker, colours which are too bright may only spoil your looks , so choose bright but make sure it is not exceptionally bright..
use 3/4th pants or jeans .. in my opinion they look pretty gud and descent in comparison to shorts on an overweight person, specially if you feel you have more fat on your hips and thighs, and do not go for skin fits .. use a little looser size they are comfortable and most of all luk gud too .
if you feel your chest part is heavy, use a sports inner instead of the regular one , they hold the extra fat / flesh in place firmly, and hence giving a sleeker look to you.
if you feel your arms are fleshy, avoid wearing tube tops and sleeveless, these only highlight the chubbyness... use elbow sleeves or 3/4th sleeves, these make your arms luk sleek too. in case if you are travelling to a hotter area, use tees which arent too tight or blose fiiting kinds.