Before you even begin to sew, you need thread. Entering a craft store, you'll notice a few brands and several different types within those said brands. Hopefully this list can offer you some insight into what each type is and what it's used for.
Types of Thread
For brands, most fabric stores will carry Coats & Clark and Gutermann. Joann's also carries a brand called Sulky. Sulky is a rayon-based thread used for machine embroidery, not traditional sewing. You can use it in a standard machine but you'll be very fed up by how easily it unravels and breaks. For this list, I'll be focussing on what C&C and Gutermann sell.
All Purpose: This is a polyester-based thread useful for most sewing projects. Because it's polyester and not cotton-based, it has a bit of a stretch and should always be used with fabric that has a natural give or when sewing bias.
Button: Specifically made for sewing buttons and is coated to prevent tangling.
Cotton: Cotton has a slightly different texture than polyester but offers no give. It's suitable for most projects as long as stretch isn't needed.
Denim/Top Stitch: Specifically made for decorative top stitching in jeans or thicker type fabric. It comes in both polyester and cotton.
Embroidery: Lightweight thread made specifically for embroidery. It can be rayon or polyester-based.
Elastic: Thread with elastic built right in. Is used mostly for gathering, smocking, or shirring.
Hand/Machine Quilting: Made specifically for quilting since it's coated to run through multiple layers of fabric. One is made for hand sewing while the other is for machine.
Heavy Duty/Upholstery: A polyester-based thread used for sewing heavy fabric such as vinyl, leather, and upholstery fabrics.
Invisible: A finicky thread used when you don't want your thread to show. It is not durable over long periods of time and can potentially melt when ironed.
Metallic: Used for decorative top stitching or embroidery. Metallic thread is finicky, can break quite easily, but can be run through a standard sewing machine.
Silk: Used specifically for sewing silk but often used for embroidery. Because it's quite fine, it doesn't leave noticeable holes in the fabric.
Once you've figured out what type of thread to use, it's time to adjust your tension, stitch length, and stitch width on your sewing machine. Depending on the fabric you're using and the type of stitch, you'll need to adjust your tension and/or the stitch length and width. But lets go over what those mean first.
Adjusting the tension wheel is necessary to balance the strength of your needle thread and bobbin thread. When you sew a straight stitch, the top and bottom thread should lay flat against the fabric and evenly spaced. If you're finding loops in either the top/bottom thread or skipped stitches, your tension may be off.
An example of loose tension
Fixing tension is pretty simple. If the needle thread is loose, you should raise the tension; if the bobbin is loose, you should lower the tension. The tension control is solely for the needle thread; thus why you have to accommodate to the tension of the bobbin. You can raise and lower the tension of the bobbin, but I personally wouldn't. To change bobbin tension, you'll have to remove the bobbin case. There you'll see a small screw. Turning it clockwise will tighten the tension while counterclockwise will loosen it. Because there is no dial it's quite difficult to bring it back to factory setting once changed; thus why I wouldn't recommend fiddling with the bobbin tension.
On occasion, you'll purposely want to loosen or tighten your tension. For example, a combination of low tension and a long stitch length will allow you to hand gather your fabric. So don't be afraid to play around with different setting to wield unique results!
If, for some reason, your stitch lines still aren't smooth despite having proper tension, you may want to rethread both the needle and the bobbin. There are various reasons as to why your thread might be warped when sewing; so if these simple methods don't fix the issue, you should break out your manual.
Determine Stitch Length
Stitch length is exactly what it sounds like: the length of each stitch in millimeters and is set with your feed dog to push a certain amount of fabric through. Your machine will probably be set to 2.5, which is the standard length, but can go from 0 through 6mm depending on the machine. A short stitch length is often used to reinforce your seams and will make your stitching harder to tear; however, it also loses its natural stretch as the seams will be quite tight. A long stitch is mostly used for basting and is much easier to remove. A longer stitch can also be used for decorative top stitching, as this won't impact the integrity of the actual seams.
An example of different stitch length
Depending on the type of fabric, you may find a longer stitch necessary. There's no official chart that connects fabric type to length of stitch, but in my experience lighter sheer-type fabrics will use a much smaller stitch while heavier and bulky fabrics will need something longer. Start with a scrap piece of fabric to test at the normal 2.5 length and explore from there! The same can be true when it comes to the type of stitch you select. Stitch length doesn't just impact a straight stitch but any stitch you choose. A long zigzag stitch will allow you to sew spandex and jersey with ample stretch; but a tight zigzag will make for beautiful satin stitching over applique.
Stitch width deals with how wide a stitch is, being directly tied to the needle placement. Just like with stitch length, you'll find on most machines that standard middle setting is around 2.5, and ranges from 0 to 5 or more. My machine goes up to 7; so the middle point is actually 3.5.
For the zigzag stitch, the width is incredibly important when it comes to the size. When you increase the number of the width, you'll notice the position of the needle move further left, thus creating a wider zigzag. The purposes of a wide zigzag versus a narrow one may vary from project to project: a more narrow zigzag is used for satin stitching, while a middle sized could be used for a stretch seam, and a wider version for joining two fabrics together.
Examples of different widths via zigzag stitch
Using the same dial or button, depending on your machine, you can choose the placement of your needle for any non-zigzag stitch. This is helpful when using specific feet or trying to put distance from something. The only confusing bit is that, unlike changing the width on a zigzag stitch where your increasing number moves the needle left, any other stitch will move the needle right with the increasing number. This is because the numbers are set at the distance from the left side of the foot. For example, 0 would be the far left, 3.5 is the middle on my machine, and a 7 would be the far right. There are several pressure foots that require the needle to not be centered; so be sure to look carefully as to not break your needle.
Hopefully you find this helpful! More posts will be added to cover the different tools and elements of sewing. Please stay tuned!
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