Good luck with what you intend, but think long and hard about the commercial flying instructor route.
I am sure you have an idea of figures, but to get to FI stage, via PPL and CPL will cost you in the order of £25k, including the hours building. FI pay is c**p in 99% of schools and job security poor. Flight training generally is very subject to economic conditions. Allowing £6k for getting your PPL, then roughly £20k will buy you an awful lot of flying which moreover will be hugely more satisfying and varied than teaching ab initio students (mostly endless rounds of "trial lessons").
You will almost certainly earn very much more doing your day job and using the surplus earnings to fly or buy a share or even a whole aircraft!
Having read this I seem very cynical! There are some who do make a career as an FI, but many tend to be those who have retired from main stream commercial aviation and many of those work part time and are self employed. Others do find their niche in commercial training organisations. Money is not the whole answer I know, but having been self employed running your own business will you really be happy salaried on a fraction of what you have the potential to earn else where?
The obvious thought here is aviation photography!! Yes, there are some very successful aviation photographers already, but success will be down to you.