1- You may start reading some fundamental principles in this book (it is easy to understand and quickly starting to implementation) and at same time try to implement them in MatLab or other programming softwares.
"Fundamental of neural networks architectures, algorithms and applications",
You can find it in some free book libraries to download.
2- Also you may find many related online free courses here,
We have shown that the fastest way to learn is by practicing "staying with the winner" behaviour or by dynamic stratified sampling with genetic algorithms but the socially efficient way of learning is by following "putting out fires" behaviour or repeated random sampling with genetic algorithms (Radner & Rothschild (1975), Mallick (1993, 2014, 2015)), as examples of mathematical-statistical mechanisms (Mallick (2007,2012)).
There is no fast way to learn anything, you need to take sometime, even machines take time to learn, and sometimes they take weeks or months to learn depending on the problem and data used.
If there is a fast way to learn then a child can become a professor in a coupe of years!
For human learning time is needed for reading, analyzing, and practicing.
Perhaps the question might be what is the best way to learn ANN?
My advice, start with easy things, and extend gradually to more complex stuff.
Read "Neural Networks: A Systematic Introduction" by Raul Rojas, concepts are developed along with its mathematical background in a very accessible way.
The fastest way to learn about the Neural Network is to trigger you brain, burn few, indeed very few like 99% of the total you have. Then definitely 99% space will become free to born new Neurons and you train those neuron, promise train in a completely nontraditional way and interconnect then in the way you heart like the most, not your brain. Remember your 99% neurons newly born but they are energetic. They can be arranged in any way you want. I promise that by this way will develop the your life time best Neural Network. I would like to use the words of world best Neural Network for your designed one, but indeed mine Neural Network is the world best. In fact for every one his/her own Neural Network is the best one.