Front loops only (FLO) and back loops only (BLO)
Usually, when you crochet, you insert your hook under both loops at the top of the stitch. However, many patterns ask you to use just one loop to create ridges, ribbing, or fancy textures.
First, look down at the top of your row. You will see a chain of “V” shapes.
Front Loop: The strand of the “V” that is closest to you (1).
Back Loop: The strand of the “V” that is farthest away from you (2).
How to work them:
1. Front Loop Only (FLO)
Instead of diving under the whole stitch, tilt your hook and insert it only under the front strand (the one closest to your body). The back loop remains untouched behind your hook.
Action: insert hook under front strand >> yarn over >> finish stitch as normal.
2. Back Loop Only (BLO)
This is very common for making stretchy hat brims! Insert your hook into the center of the “V” and push it out the back, catching only the back strand (the one farthest from you).

Increase (inc)
To make a flat circle, a hat, or a stuffed animal, you need to add more stitches so the fabric can expand. This is called an increase. While it sounds technical, the secret is simple: two stitches go into one hole.
Insert your hook into the next stitch (1) and complete a single crochet (or whichever stitch your pattern uses) just like normal. Do not move your hook to the next empty space yet! Insert your hook back into the exact same space where you just placed the first stitch. Complete a second stitch right there (2).

Invisible decrease (dec)
Standard decreases often leave small, unsightly holes in your work. The invisible decrease solves this! It merges two stitches into one so seamlessly that you can barely tell where it happened.
The golden rule: For this stitch, we focus strictly on the front loops (the loops closest to you).
Insert the hook in the front loop of your first stitch and in the front loop of the second stitch (1). Wrap the yarn over the hook and draw it through the first two loops on your hook (2). Wrap the yarn over again and draw it through the two loops left on the hook (3). Now you’ve finished one invisible decrease.

Bobble stitch
The bobble stitch, also known as a cluster stitch, adds some dimension and fine texture to your crochet fabric. The entire idea of the bobble stitch is that you partially complete the amount of double crochet stitches indicated in the pattern (usually 3, 4 or 5) – all in the same stitch – and then wrap yarn over and pull the yarn through all the loops on your hook.
So, yarn over the hook, then insert your hook into the next stitch (1). Draw the yarn through the stitch. Now there are three loops on the hook. Wrap the yarn over the hook again and pull it through the first two loops on the hook. One half-closed double crochet is done, and two loops are left on the hook (2). Repeat the previous steps twice in the same stitch. Now you have four loops on your hook. Wrap the yarn over the hook and draw it through all four loops on the hook (3). One 3 dc bobble stitch is finished. Create a bobble stitch with as many dc stitches as your pattern requires.

Magic ring
A magic ring is a perfect way to start working in the round. You start crocheting over an adjustable loop and finally pull the loop tightly when you’ve made the specified number of stitches. The advantage of this method is that there’s no hole left in the middle of foundation.
Start with the yarn crossed to form a circle (1). Draw up a loop with your hook but don’t pull it firmly (2). Hold the circle with your index finger and thumb, and wrap the working yarn over your middle finger (3). Make one chain by wrapping the yarn over the hook and drawing it through the loop on your hook (4). Now insert your hook into the loop and underneath the tail. Wrap the yarn over the hook and draw up a loop (6). Wrap the yarn over the hook again and draw it through both loops on your hook (7). You have now completed your first single crochet (8). Continue to crochet sc until you get the desired number of stitches. Now seize the yarn tail and pull it to close the ring hole (9, 10).
Instead of magic ring, you can make 2 ch, and, further, crochet the required number of stitches in the second chain from the hook.

Invisible color change
Have you ever changed colors and ended up with a jagged, messy line where the old color bleeds into the new one? This technique fixes that.
The golden rule: To get a perfect switch, you must introduce the new color before you finish the old stitch.
Crochet the next stitch as usual, but don’t pull the final loop through (1). Instead, wrap the yarn in a new color around your hook and pull it through the remaining loops (2). To make a neat color change, you can use a slip stitch instead of a single crochet. Don’t pull the slip stitch too tight or it will be difficult to crochet into it in the next round.
Two “Pro” tips for cleaner work:
- The slip stitch trick: If you are crocheting in a continuous spiral (like amigurumi), stripes can look like stairs. To smooth this out, make the very first stitch of the new color a slip stitch instead of a single crochet. This lowers the height of the row and hides the “step.” (Just keep it loose!).
- Carrying the yarn: If you plan to use the first color again in a few rows (e.g., thin stripes), don’t cut the yarn! Leave the old yarn attached and hanging inside your work. When you need it again, simply pick it back up. This saves you from having to weave in dozens of loose ends later.

Fastening off
When you complete a piece of your crochet project, you’ll need to fasten off the yarn and secure it so the stitch will not untwist. To do so, cut the yarn leaving a small tail. Then, with your hook, draw the tail through the loop on your hook (1). Remove the hook and pull on the tail to tighten. With a tapestry needle, weave the tail through the stitches of the fabric to hide it (2), or leave a tail to sew the pieces to each other.

(Source: amigurumi.today)