As has been said, firstly get your Class 1 medical.
You have a few choices, one is to apply for one of the sponsored airline programmes. Not only do these fully fund training, the fact that the airline is paying means that the airline has a vested interest in giving you a job at the end. The downside is that they are extremely competitive. Aer Lingus allows you to apply after having sat ATPL theory exams, which may be useful to note.
There's also the self-funded "mentored" programmes but the airline won't necessarily have the same interest since they're not paying for it.
The modular route around your current job is viable, it's what I'm doing at the moment. You have quite a bit more flexibility around when you qualify, if the market is slow you can drag things out a little bit and at the end of you don't get a job straight away you can stay in your current job without as much pressure. If you're on a 40 hour work week, expect a combined 60 hour work/study week, especially during ATPL theory. There is a blog about modular pilot training written by someone who was working in IT during training which you may find of interest.