PLAYING CARDS IDEAS.
Note how a center oval can be blended with an outer frame - both elements would occupy the center of the card.
Note fern design - can be linked together to form a border.
Note how oval shape can be blended with an outer border - in the example the effect is slightly masonic.
Note how a white border can stand out on a dark background - a string of pearls can make a good border.
Possible corner design element to be mirrored on the other corner.
A nice old background element that could be used in some sections, adapted perhaps for Sherlock Holmes - such as small silhouettes in the middle of each square.
An example of text on banners: "The Sherlock Holmes Museum London" or "221b Baker Street."
An example of text on banners.
Note the middle rectangular border - the silhouette could sit in a similar frame, with or without the flowery pattern. Note the arrow design near the edge of the ceiling (top left of image). Note the rectangular side panels separated by a circle - text could be placed in these panels.
Note the fans in the corners - same thing could be done for the playing card. Note the black center circle design - it could be stretched to an oval border for a silhouette.