You will quickly learn that building and training neural networks takes more than one attempt. Usually, the first version of your model will not work as well as you hope. It requires quite a bit of experimentation to come up with a great model.
A good neural network starts with a great dataset. In nearly all cases, better performance is achieved by using a proper dataset. Many data scientists will tell you that they spend about 80% of their time working on a good dataset. As with all computer software, if you put garbage in, you will get garbage out.
Even with a good dataset, you still need to spend quite some time to build and train different models before you get the performance you're after. So, let's see what you can do to improve your model after you've built it for the first time.
After you've trained the model for the first time,...