The EXTRAS submenu lets you change the appearance of the display:
<2=N;> Set: Y,X,C,S,G,G+,K,J,Mu,An,Ou,Ex? <G+>: EX
\* Options are:
1) Text: Size, Color, Title, Labels, Move
2) Curve: Symbols, SIze, Fill, Lines, Color
3) Grid: Screen, Ticks, Grid, Color
4) High Resolution <Off>
5) Color <Off>
6) Overlay of separate pages for the grid, each symbol, and fits
<3=X;> Set? <C>: