Do keep in mind that while I've only been working from these patterns, I'm still kind of new to this, so for those who have experience with these patterns (and in Japanese), if I've missed out something or got something wrong somewhere, please feel free to correct me! :) Now that's out of the way, let's get started!
*This guide uses US stitch-terminology.
INTRODUCTION
Japanese ami patterns usually look like this:

You may also see a stitch-counting guide at the side of the pattern, which shows how many stitches you should have in each row. It also tells you how many stitches to increase or decrease and when to keep the number of stitches constant, so you don't have to waste time counting the number of stitches in the pattern.
STITCH-GUIDE & TERMINOLOGY:


There's a whole list on a Japanese-English lexicon here which was posted up sometime back.
PATTERN-READING:
Patterns read anti-clockwise, so the stitch on the left of the row number is the starting stitch of the row, and the last stitch of each row is on the right of the row number. Do note that the circle highlighted in red refers to the magic ring that you start from, and the first row consists of the six stitches you started off with. Also, there may be patterns that require you to chain six stitches instead of creating a magic ring with six stitches, and when this happens, there is no Japanese character (pronounced "wa", meaning circle) in the middle of the circle.

After a couple of rows, probably to save space, the first few and the last few stitches of the pattern will be shown as a rough guide. The stitches marked out in blue correspond to each other, showing where the guide ends and the rest of the pattern is not shown. When you decrease, eg. in row 6, simply follow the pattern shown for the first 5 stitches (sc, sc, sc, dec) and apply it to the rest of the row.
*The method of starting a new row here is actually a slip stitch followed by a chain stitch, but I'm not sure why they would do this, because I've tried it and it forms a visible line of different stitches (and causes my teddy bears to look like brain-surgery patients!). There are certain patterns where they call for both this method and the usual way of starting a new row (ie., crocheting the first stitch of the new row instead of doing slst+ch first), but I haven't tried that so I don't know the difference. If anyone could shed light on this issue, that would be great as I'm personally quite curious about it.

At the end of the pattern, you should have the number of stitches as stated. Sometimes the instructions will call for you to stuff the part and sew it up.
That's pretty much it, I think. There's stuff I can't really explain here, but which is also quite secondary (e.g. stitching the parts at certain positions - it's pretty commonsensical and you could probably easily figure it out yourself). Hopefully I haven't missed out anything. If there's anything you need clarification on or anything I missed out do tell me. Happy ami-making! :)
Credits: The pattern scan used in this guide was taken from: ちいさなかわいいあみぐるみと小物 (Small and cute amigurumi and komono), ISBN 978-4-8347-2761-6.
*Updated 06/07/2010
February 9 2009, 16:35:14 UTC 4 years ago
Thank you!
February 10 2009, 02:37:54 UTC 4 years ago
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February 10 2009, 02:38:12 UTC 4 years ago
February 9 2009, 17:25:29 UTC 4 years ago
February 10 2009, 02:38:52 UTC 4 years ago
February 9 2009, 18:46:40 UTC 4 years ago
February 10 2009, 02:36:19 UTC 4 years ago
February 9 2009, 19:17:01 UTC 4 years ago
February 10 2009, 03:00:09 UTC 4 years ago
February 9 2009, 20:12:10 UTC 4 years ago
You rock!
February 10 2009, 02:37:07 UTC 4 years ago
February 9 2009, 22:45:56 UTC 4 years ago
Also just wondering if there's a reason why you made this post friends-only? Would you consider unlocking it so that the world can see and the search engines can index it? =)
February 10 2009, 02:32:43 UTC 4 years ago
I made it friends-only because I scanned the pictures from one of my own book. I'll credit the book later when I've access to it so I can unlock the entry. :)
February 9 2009, 22:54:38 UTC 4 years ago
even though my boyfriend is majoring in japanese language.. he doesnt know essentials like stuff for my crocheting! boys right? hehehe :)
February 10 2009, 02:34:25 UTC 4 years ago
February 10 2009, 16:30:37 UTC 4 years ago
February 10 2009, 16:57:58 UTC 4 years ago
May 12 2009, 16:17:25 UTC 4 years ago
June 10 2009, 15:45:00 UTC 3 years ago
need a little bit of help
http://babelfish.yahoo.com/translate_uri was wondering if you could help me with #4 and #5?
how it goes outside of the circle, but doesn't complete the full circle, does that mean it's just going back on itself?
thanks in advance!
June 11 2009, 01:13:05 UTC 3 years ago
Re: need a little bit of help
I'm not really sure what you mean by going outside of the circle, and I haven't really been making amis for sometime, but I think it goes like this:You start off by making two circles and when you've completed the 5th row, you join the two circles together at the highlighted stitches. For the 6th row, you would work them as one whole piece.
Hope that helps! If not there are other experts here who, I'm sure, will be able to help you better. :)
October 10 2009, 20:21:16 UTC 3 years ago
October 17 2009, 19:53:30 UTC 3 years ago
Just used your guide,
so helpful!!!January 5 2010, 21:08:56 UTC 3 years ago
January 6 2010, 04:12:42 UTC 3 years ago
July 5 2010, 22:19:58 UTC 2 years ago
chain/ slip stitch row start
I think you read the pattern a little off, because for all Japanese patterns I've used like this the chain stitch starts a new row, and the slip stitch ends it. So for example the last stitch in row ten is a slip stitch, and then you start row eleven with a chain stitch.Don't know if you were still curious about that but I thought I'd post this anyways :)
By the way, this guide was really helpful!
July 6 2010, 14:57:01 UTC 2 years ago
Re: chain/ slip stitch row start
Oh yeah I got that bit wrong. Thanks for correcting me on that. Have you noticed that there is a different "look" on it though, as compared to simply going into a new row with a single crochet?2 years ago
December 20 2010, 06:14:22 UTC 2 years ago
sl1, ch1
i just happen to know that this method (instead of just working continuous rounds) helps make color changes seamless :) instead of the odd step-like stripes.WONDERFUL guide :D
December 5 2011, 06:22:11 UTC 1 year ago
starting point
thanks so much for this! I have a question though if you could help?I just need a small clarification on the first step of starting the head of a hello kitty pattern. There's no 'wa' symbol so it seems you don't do the magic circle, just chain 8. Then it says to single crochet around but you're supposed to end up with 18 sts at the end but I only have 16...:o