..one way to do this is to use "tput" and "terminfo" capabilities, if these are available. terminfo allows for the definition of colour attributes, and tput can access those definitions.
"tic" and "infocmp" are the methods used to compile and discover terminal capabilities.
Here's an example, using BOLD rather then a colour, assuming that smso and rmso have been defined in the terminfo database.
BOLD='tput smso'
NOBOLD='tput rmso'
echo "${BOLD}1 ${NOBOLD} - Option 1"
echo "${BOLD}9 ${NOBOLD} - Exit"
Another (primitive) way is to discover the actual terminal codes for displaying colour and embedding them in a script, but I wouldn't recommend this.