As an "improving" organist myself, I have a question: if you play church organ regularly, how long did it take you to get good at it (good enough to play hymns consistently well for each Sunday), especially if you didn't play organ or piano consistently in your youth?
Oooh ..Ild like to know the answer to this too Ive recently being asked to see if I can play the organ, but our church has an electronic organ with no pedals. I struggled through to grade 7 on the piano a child, but only play occasionally privately at home now, when I am reasonably sure no one else can hear me. I am not at all confident about it. Ive chosen about 40 hymns to try to learn over the summer to give myself a basic repertoire. Since they are arranged assuming an organ with pedals I sometimes need to adapt them slightly as I go, Im beginning to wish that the church organ did have pedals because I think it would make some of them easier. I can play them quite happily when I sneak down to the church to practice, and have arranged to sit with the current organists after the summer to get a feel for what stops they use, what volume to play at etc., but I havent tried playing during a service yet and I think that will be the hardest step.
I found I got better pretty quickly. A big part of it was confidence and once I got past feeling like I was going to throw up and poo myself at the same time, I could play reasonably well with only a little bit of practice. It probably took 2-3 months and after about 6 months I just played them quickly on the piano on Sunday morning before I left for church. As for volume, I played them loud! And briskly!! Especially if it was an unfamiliar tune. Sometimes I would play the tune on a loud stop and the accompaniament more quietly. I found people needed the encouragement to sing.
I played the pedals for some of them. I'm not a "proper" organist, so I don't think this is a recognised technique, but I would take my shoes off and warm up the doh and soh pedals between the hymns so I knew where I was!