If there's no value printed on the chips, then you are free to make up your own. If you use the same setup each time, then all will be well.

Standard casino denoms are $1 for white, $5 for red, $100 for black. If you want to use those three, use your blue to represent $25 chips. ($25 are usually green).

If you want higher values, like I said, just make em more. You can have $100 red, $500 blue, $1000 white, $5000 black. You can do whatever you want.

The most important advice, I repeat: ALWAYS try to use the same denominations every time. If everyone gets familiar to "red=$5", then there should be no problems. Consider posting a little sign where you play that lists the denoms.

-g