It sounds like what you're doing is right... Sometimes it just takes a while. Under a year is considered normal, though about 80% of women with no fertility problem will become pregnant in the first 6 months of trying.
For now, try to learn your cycle and then know that about 17 days before you get your period, for approximately 5 days, is your most fertile time.
Once you've been trying for a full year, it's worth making an appointment to see if there might be a fertility issue - but not before then, unless you're over 35.
Good luck!
Rachel Inbar
www.FertilityStories.com