The easiest thing to do is start with a bike that fits you well and go from there.
Take measurements of the current bike and compare to the posted measurements of the bikes you are considering. The biggest thing to look at is the c-c top tube measurement with horizontal top tubes or the virtual top tube measurement with sloping top tubes. These are the main things that take into consideration your height (waist down) and reach (waist up). Then there's things like head tube angle, seat tube angle, bottom bracket height, etc that make smaller differences in fit. Lots of things to consider.
Once the bike is chosen and in your possession you can make some small tweaks with stem length/angle, seat height, type of seat post, position of seat...