X means the strings are muted with your hand, O means the strings are played open - while the black strip means you use your index finger to bar across several strings.

Its not really about the name sandra but its mentioned in mambo no.5 by lou bega :)

I liked cooking and art because I was so bad at both of them it was laughable and because I didn't improve no matter how hard I tried I started messing around with flour, paint and stuff and it just got funnier and funnier XD