The first thing you'll want to do is sit down with a pencil and paper and start counting up the money you want to make for the various things that are required. Speak to whomever you need to about this. As the numbers add up, you'll start to get some idea of what kind of fundraiser you need to be doing, and how much each person on your fundraising volunteers team needs to be responsible for.
Once you know what you're up against, you can start looking for some PTA fundraiser ideas that will help you get to your goals as quickly as possible. If that means turning a high profit with a small group, then you'll want to go with something like scratch card fundraisers, which have some of the highest profits out there, and work fantastically well for small teams fundraising. If you have a larger team to reach a more substantial target, something like brochure-based fundraising can work extremely well.
Once you have gotten yourself organized and know what your plan is for fundraising for PTA, let your plan play itself out and just keep tabs on it as things develop. Once you have a solid foundation set out for fundraising for PTA, you can relax in the knowledge that you are on the path to success, and enjoy the rewarding results of having chosen a PTA fundraising idea that works well for you.