When you go to print the pop up window (that asks how many copies you want to print etc) should have "properties" available top right. Click this and assuming your printer has the ability to print in B&W you should see the option here.
I should however warn you that the majority of printers on the market will not allow you to print unless you have a full set of cartridges installed. If I could trouble you to let me know the model of your printer I may be able to offer some further advice.