How can I do personally onboarding?

The product that I’ve built started to get some attention and sign ups but people leave without using it. The reason is probably because of the longer setup time. Since I couldn’t reduce this duration, I decided to personally onboard people who are interested. So I cant throw the product out there and expect people to become a long term user. But how can I get people to trust me and be patient before finishing the setup?

Author: BoysenberryNo5650