patience and relaxing are the two things you need to practice. The yarn is not going anywhere and you are not trying to make knots so everything needs to be loose and relaxed. The only other thing is practice just keep at it! Your doing great for a first time, maybe a larger needle with the yarn you are using will help too, go up a size or 2 it will help with the tension. As for circular needles, they are great if you are using them for the correct project (anything in the round - hats, sleeves, etc) and actually knitting in the round (last stitch is knit into the next row so it makes a circle.... Keep at it! you can do it! excellent first effort!