In case you're curious, read on...

Sites like astro.com and astrotheme.com will provide you with your natal chart that includes your rising sign, which is determined by your time of birth. 

You read for your rising sign because the transiting planets are falling into a specific house system unique to each rising sign. That's not to say you can't look to other aspects of your chart for transits.

Word of advice... do not use the astrological table for determining the rising sign - it may not be accurate because location is one of the factors that are taken into account in mathematical calculations.