Here is what helped me start biking and what boosted my confidence:
1) Positive attitude. I wanted to start biking partially to get physically healthier, but also for my mental health. I make sure I have fun riding, because that makes me want to keep riding.
2) Peer pressure. I like riding alone, but when I ride with other people it makes me a better cyclist. The companionship is great, and it's good to have someone pushing me. My mom definitely helps me become a better rider, just with simple words of encouragement. Riding with other people of all skill levels is helpful. And not all companions have to be human - a dog running beside you can be the perfect partner.
3) Set a realistic goal. This can be anything from riding 50 miles a week to riding 1,000 miles a year. My personal goal is to someday ride in the Ride Across Iowa.
My most recent bike ride was on Seven Bridges Road earlier this month. I consider this my first "adult" ride. The conditions were absolutely perfect: sunny with just enough wind to keep you cool. My mom and I headed out for a 10-mile ride. My mom has a really good Scott bike, while I have an old second hand Fuji. We switched bikes at the halfway point so that I could test out her lightweight road bike. After this experience, I know it's important to invest in a good quality, lightweight bike if you are serious about biking. My top speed on my mom's bike was 21 mph.
Our bike ride was a success, and I look forward to further training with my mom, and even training for Iowa.
I hope this motivates you to go for a ride and remember to always wear your helmet!