In British Council’s website, there is a section where you can practice English in every skill, including listening. Follow the given link! There you’ll find listening skill practice page which is comprised of exercises in the form that is similar to the IELTS test. You can start with Level A1 then move on to Level A2, Level B1, and Level B2. I truly believe that if you can finish all the exercises, you will significantly improve. IELTS will no more intimidate you.
Another valuable source for improving you listening skill is TED, a nonprofit organizing an event in the form of short, powerful talks. TED is very useful because each talk lasts only 18 minutes or less. It covers diverse topics from magic tricks to neural science, with subtitle in almost every language. Choose a video that matches your interests and watch it with English subtitle. Watch it again without a subtitle. The link to TED website can be found below.
The very first thing to do for the beginner is to get used to the rhythm and melody of English, which is significantly different from Thai. Go to the sites given below and put in the earbuds or just leave the speaker on. You don’t have to pay attention to what you’re listening all the time. Just let the rhythm and melody of English sink in.
IELTS Listening Skills : This is my personal experience. I am sure it would be helpful for you as well.