The very best advice I can give to any agent is that lead generation, listings and leverage are the THREE main ingredients to a very successful real estate career. You must prospect every single day with NO exception. This must be done prior to 11:00 AM with no interruptions. Every listing marketed properly (sign tags, info tube flyers, classifieds) should produce at lease one closed buyer, so concentrate on your listings!
Your leverage (using assistants, buyer agents, etc.) are important and you need a system to make sure you constantly train them so they can be effective at their job. Your systems and procedures should be developed and implemented by your staff, and they should represent how you want to run your business.