Please and thank you. Be very liberal with these two phrases. Your mom was right. Be polite to everyone consistently and it will come naturally. Waiters, valets, and cab drivers are all people just like you. She will notice.
Open doors. You would be surprised how much single women appreciate this. Most of your competition won't bother. Good. Get out of the car, walk around and open her door. (Don't be staring at her legs as she gets out.) Always extend an arm to help her in or out of a car or a chair. On the way back, unlock her door and let her in first. Walk ahead to doors and hold them open for her as she enters or exits. Always hold doors for her when possible, but in any case NEVER use one ahead of her. Get in the habit of always doing this. It really sets you apart.
Push her chair in. A gentleman always stands when a lady enters or leaves a room. This is especially true at a table. Rise and pull her chair out as she stands up. When she returns, rise again and push her chair in as she sits. If you have to leave say, "Please excuse me." When being escorted to a table or a seat by an usher or hostess, the man follows the lady. If there is no assistance, the man leads and escorts the lady into the room. If the two of you are walking in together she should be on your right. If it's a formal occasion let her take your right arm. Always offer to help her with her coat. Always offer to walk her to her door at the end of the evening.