Amigurumi Basics by a Beginner V: 5 More Basic Stitches & Techniques

Here're five more basic amigurumi techniques (click here for Part I):

7. Magic Circle or Ring

See my earlier post on how to do the magic ring

Now that you've mastered the single crochet, let's go back and learn the magic ring, the preferred way of starting an amigurumi round.
Also called: adjustable ring, magic loop
Good to know: You can substitute the initial "Ch 2. __ sc in 2nd chain from hook" instruction with the magic ring, doing the designated number of single crochets in the ring.
Tutorial: Check out my previous post.

8. Increase
Abbreviation: inc
How to: If you know how to do a single crochet, you know how to increase. Instead of working one single crochet into a stitch, you do more than one, which will increase the overall width (in rows) or circumference (in rounds).
Sometimes the pattern will just say "2 stitches in the next stitch", instead of "increase", and that's exactly what this is.
Purpose: Increasing (and decreasing) helps shape your amigurumi.
Good to know:
• Usually you will space out your increases evenly across the round. In patterns, for example, you'll see:

*1 sc in the next 2 st, inc* repeat 2 times 

We'll look at deciphering patterns later, but the above basically means:

Stitch 1: 1 single crochet

Stitch 2: 1 single crochet

Stitch 3: 2 single crochets in the same stitch (= increase)

Stitch 4: 1 single crochet

Stitch 5: 1 single crochet

Stitch 6: 2 single crochets in the same stitch (= increase)

In your previous round, you have 6 stitches, and in this round, you'll have 8 stitches because of the increase.

• It's important to keep your increases gradual and incremental. If you increase too drastically right away, you'll end up having a bunched up look.
• Increases are easy to do, but keeping track of how many stitches you've done and when you need to increase can be tricky in the beginning. Try a stitch counter.

9. Right Side and Wrong Side
• The "right side" (abbreviation: RS) = the front of your piece
• The "wrong" side=  the back.
How to tell: The stitches look different (check out the video below)
Another quick way to tell in amigurumi that is worked in rounds is that the side with the yarn tail from your magic circle sticking out is the "wrong" side.
Good to know: Whether you choose to show the right or the wrong side of your piece to the world is really up to you, and unlike the names, there really is no right or wrong. To ensure your amigurumi's surface looks uniform, you just have to make sure that all your pieces have the same side showing.
More information and comparison: 
• All About Ami 
• Video from Nerdigurumi comparing the differences. Interestingly, the sizes and shapes of the balls change depending on which side you've showing:

10. Front Loops and Back Loops
You will come across instructions that tell you to work in a specific part of a stitch, so what are they talking about exactly?
Let Stitch Diva Studio explain with a photo tutorial.

Source: Stitch Diva Studio

Good to know: Stitches that are worked in, for example, just the front loop, will look different from stitches that are worked in, say, the back loops. Crochet makes use of the different looks to add texture to your piece.
Take a look at this Crochet Spot's comparison.

11. Decrease
Abbreviation: dec, sc2tog (single crochet 2 together)
We saw how an increase makes the "circle" get bigger earlier. To make it go smaller, you'll need a decrease. Here, you're trying to join two stitches in the previous round together by making one stitch only.
How to:  
1. Skip a stitch: generally not recommended because of the hole you'll leave in your piece.
2. Insert the hook into one stitch, yarn over, and draw up a loop. You don't complete that stitch, but insert the hook immediately into the next stitch, yarn over, and draw up another loop. Now you've three loops on your hook. You yarn over, and pull through all loops at once.
However...
I've never done anything but Planet June's invisible decrease to make sure the amigurumi looks as good as it can without too many bumps and holes caused by the decrease.

Source: Planet June. Click here for the left-handed version

You can also check out All About Ami's photo tutorial on how to do an invisible decrease.
p.s. An invisible decrease requires you to work in the front loops, hence all that talk earlier about parts of a stitch.

Putting it all together: Let's crochet something already!
Now that you have all these stitches and techniques in your bag, let's try doing a common sphere shape, which will make use of the magic circle, single crochet, increase and decrease.
I find following videos and crocheting along is one of the best way to learn. Reading instructions can give you a headache sometimes, but if you've someone there to guide you through it's a lot less painful.

Here's one version of crocheting a ball. You'll find others on youtube.

Video from unwindpatterns

Note: The crocheter in the video uses two different decreases techniques. You can see how your piece will look, and you can also substitute one row with the invisible decrease and see which method you like better.