Having also been a candidate for the presidency....here are my thoughts.
Be a leader. Be on time, prepared, and in attendance at everything. You are the prime example for your chapter and if you don't show that....the chapter won't follow.
Be open. Be willing to talk to the members about everything, whether it is recruitment, HB issues (obviously confidential between her, HB, and you), personal problems, finances, EVERYTHING! They need to see that you care about the chapter and also that you care about them as individuals and as your sisters.
Be helpful. Allow younger members to shadow you in order to let them see what it is like to have a large position on CMT. Offer help to other officers (CMT or directors) especially if they have an event coming up. Keep your advisors and nationals up to date on anything that is or might be going on that needs to be addressed.
Always ask for help if you need it!
Have a good relationship with Greek Life. The office personel, other members (NPC, IFC, NPHC), and exec council members. Make yourself known to them so they don't say...."who's the president of DG? oh that girl? who is that?" (trust me....it's happened!)
Be accessible at all times. I know work and class, etc. present challenges to having such a large office, however, the members of your chapter need to know that you are accessible to them when they need you. Return missed phone calls as soon as you get them, take action if something needs fixed or something has happened. Be prepared at all times to be the #1 person on everyone's list.
Be experienced. I have seen many presidents go by that have never served as a VP on CMT. They served in a director position but had no idea what they got into. Have some sort of leadership experience to back you up. CMT, Panhellenic, etc. They look for this leadership because they know that you are knowledgeable about what you are doing.
Most of all though.....have fun. Yes this position can/will be stressful at times, but you don't want to always feel bogged down. Take some time out for yourself to hang out with the girls, go home, spend time with a boyfriend, etc. It'll most likely keep you from burning out by the end of the year.
I wish you the best of luck if you pursue this and if you need any more advice or have questions, please feel free to ask!