Sewing a Straight Line
The more you sew, the easier this will become. Check your seam allowance, and rather than looking at your needle, focus on keeping the edge of your fabric aligned with the appropriate mark on your needle plate. If the plate does not have lines etched into it, make your own by applying masking tape in the desired position.
Check Your Bobbin
While you can see when your top thread is likely to run out, the same is not true of the bobbin. It is worth checking that there is enough thread on it to finish the seam you are about to sew before you start, particularly if it is a challenging part of the project.
Reverse Stitch
Start off your sewing about ½ cm from the edge of your fabric and stitch back to the edge before sewing the seam. When you get to the other end of the seam, reverse for a couple of stitches again. This fixes the thread so it will not unravel.
Practise on Scraps
After cutting out your pattern pieces, use scraps of fabric to practise stitching, and adjust the tension and stitch length as needed. Cotton fabric will require different settings from heavy wool fabric, so practise on the fabric you will be using.
Hold On to the Ends Of Your Thread
When you start a seam, hold the ends of the thread in your left hand to ensure the fabric is not pulled down into the plate under the needle. Particularly with sheer fabrics, this can mean you have to cut the fabric to remove it, which can be disastrous since you would have to cut two more pattern pieces.
Control Your Speed
Using the foot pedal of your sewing machine is rather like driving: when you are used to it it becomes second nature, but at first it can be hard to control the speed. Go slowly and be gentle with the pedal. According to Simply Sewing Magazine, the pedal is pressure-sensitive, so the harder you press down the faster the motor will run.
Press
Always press seams to ensure a professional finish to your project. Before crossing a seam, ensure that the first one is pressed open or to the side.