The whole process was very smooth, I applied through their website and expressed my interest in teaching despite having entry-level experience and I did an online interview with the employer (aka the principal) to let her understand my experience + getting to know how the job scope is like and afterwards I had to arrange for a 45-min entry test at one of the ARTARY outlet near my house.
The test includes drawing, colouring, painting and using of oil pastels on a A4 worksheet which doesn't require any hyper-realistic professional drawing standard as we are simply tested on our basic proficiency in art.
After the test, they arranged a 2-lesson observation class which is about 3 hours long (1 lesson = 1.5h) so I had to observe the 1st lesson for the class along with an experienced teacher and then have a try at teaching 1 class on my own. If you have to confidence to handle kids, it shouldn't be an issue because the class structure is the same as the 1st lesson and all you have to do is make sure your class is managed within the lesson time. Once done they emailed me a freelance contract which I had to look through and sign.