Aye, a throwing knife need only be made of mild steel, 1/8" thick which you can cut out with a jigsaw and sharpened on a bench grinder if you dont have many tools. I have made several, and put leather handles on them because fancy handles just come off.
My needs and perception in the hobby have changed to where I no longer use or carry my throwing knife, and choose to carry a forged blade matching that of an 18th century knife. But, I have thrown a knife a few thousand times I suppose.
I can help some in teaching.
The trick is to throw with the same release point and motion every time, consistantly. The consistant part will take time in practice.
Once you are throwing consistantly (even if you are not sticking), adjust your distence closer or further away from the target.
Another trick is, the knife (and hawk) needs to complete one revolution after it leaves your hand. If you are too far away, your knife will spin more than one rev and hit the back of the blade or the handle coming back around.
If your too close, the blade will hit the knife's edge flat, and you need to scoot back.
Start with mini steps to adjust. A half step can go a long way with throwing a knife.
Hope this helps.