My specialty is working with pre-seed, tech-based B2B companies who are interested in becoming investable.
Short answer is approach it in this order depending on how far along you are: self-funded, friends & family, accelerators, angels, vc. Each will be subsequently harder to attract. Without knowing more, it is very difficult to provide a great answer here, but traction is key. Traction based on customers using your product and paying you to use your product.
Finally, when you say 'everything is done,' what do you mean by that? You are never truly done so my suggestion is to be much clearer in your status when communicating.
I hope that helps give you some initial thoughts, but again, I'd need a lot more information to provide a better answer.