How to better my chances of getting a job?

i applied at a recycling center on friday. The guy who does the hiring seemed pretty happy with my experience. He sat me down and talked to me while he read over the application. Once he noticed i have forklift and hazmat certification he said he would definetly call me soon. They are closed today but they open tomorrow at 9 am. Should i call them to check up on the application? When i originally applied the opening was for a part time position but he offered me full time right off the bat. What can i do to show them i really want and need the job?