Much like in everything else, kayaking involves proper technique and if you want to become good at it you would have to apply this technique as much as possible. There are two aspects to kayaking technique that you will have to pay attention to, both of which are essential both for becoming good at kayaking in general as well as if you want to stay safe while you are having a good time.
The first aspect of kayaking technique you should keep in mind is posture. Sitting upright is essential because it helps you focus strength into your core which would get more and more resilient as you practice. If you slouch you would making your arms do all of the work. Your arms are important, but without the support of your core they would not be of much use, so sit upright and give your arms some help so that you can maintain a little more control. Additionally, slouching can cause back problems because your lower back would be tensed up all of the time. This can lead to chronic back ache in the long run, so if you want to keep kayaking for a long period of time avoid doing this.
Another important aspect of kayaking is paddling technique. You should try to develop a rhythm while you are paddling, one that would allow you to distribute force evenly and move at a steady pace. Being inconsistent in your paddles would make it difficult for you to move at an efficient pace which would take quite a bit away from your overall kayaking experience.
If you want some more tips and pointers, read up on inflatable kayak reviews. They contain a lot of information about proper technique in addition to product reviews.