The best I can tell you is that only knights, nobles and royals had crests and they were bestowed upon them. THE VAST MAJORITY of families NEVER had a crest. If you want to prove that crest ever belonged to your family, it will be in a heraldry book ...
There will be many versions of one family's crest. Traditionally, the family crest is altered by combining elements of marrying families and creating a new version. Looking up my family name's crest, i found that it doesn't look much like the one han...
Find out what style of dancing is typically danced at those mixers and take some classes in that style. I'm sure you can find something in your local dance studios or maybe some evening classes in community colleges - usually you don't have to enroll...