Technology: Keep it up-to-date for Gen X to stay productive. For Gen Y encourage suggestions and don't fear change. Gen Y is more comfortable with technology than any other group. Learn from them.
Compensation: Be willing to negotiate with Gen X and offering perks if you can't budge on compensation. For Gen Y, highlight the importance of building their resume instead of their bank account. An impressive work history can make all the difference in a slumping economy.
Attire: Give Gen X a heads-up if they should dress nicer for specific meetings or customer interactions. Since Gen Y are new to the job market (and might be oblivious to your company's culture), let them know that dressing better will help defeat "slacker" misconceptions, build credibility with executives, and help their career over the long haul.
Work Ethic: Trust Gen X and understand that the flexibility to telecommute or work outside business hours will help you gain their trust. Appeal to Gen Y's career goals. Accept the inevitable that by the time this generation is fully in the workplace, the standard work week will likely be replaced by a new set of rules based on productivity...not hours at their desk.
Source: Business@Work, BusinessWeek, August 25, 2008