Looking for some opinions

I start school on January 28th after taking about 3 years off of school. I have decided that I would like to go on to Grad school and possibly get my phd so I can teach at the university level. I am 26 now and finally getting started towards my ultimate goal. Just wanted to know if anyone had any advice for me or possibly a better idea. I know it will be a long adventure just hoping I can do it.