How to Choose Bike Shorts
The most important features of bike shorts is their lack of seams in the crotch, and extra padding to increase comfort while riding. Bike shorts should be made from flexible fabrics that move with you and don't bind while pedalling.

Bike Shorts - Buying Tips
There are a variety of bike short styles and designs, including those that look like regular shorts with a padded inner liner. The best way to choose the right bike shorts for you is to decide the type of riding you intend to do most often and buy shorts for that purpose.
                        Set a Budget - Bike shorts can range from $30 to $300, so try to set a budget before you shop.

                        Tight or Baggy - Consider tight-fitting race shorts if the majority of your riding is fast cycling on the bike. This offers the most comfort and aerodynamic fit. If you spend time off the bike, tour or commute by bicycle, need pockets, or are more concerned with the look of the shorts than your speed on the bike, then "baggy shorts" with an inner liner would be more suitable for you .
                        Number of Panels - Less expensive shorts usually have fewer panels of fabric, while the most expensive and form-fitting bike shorts can have up to ten panels.

                        Waist Band or Bib - You can buy bib shorts that offer shoulder straps, rather than an elastic waist band. Some people find this style the most comfortable after hours of riding bent forward at the waist. This is the choice of all pro riders.

                        Chaffing – Wearing good bike shorts will increase comfort but if chaffing is a problem then consider the use of a “chamois crème”. 

                        New to Bike Shorts? - Keep in mind that bike shorts are meant to be worn without underwear.

                        Cycling Tops - Whilst shorts are a "must have" for the regular rider, a good cycling jersey will also aid comfort.