Now to the part that concerns your own coord choices on how to avoid wa-lolita fail. Before that, in case you just found this entry via google, here are the previous parts.
For this entry I put together the worst, itasomest coord I could think of, trying to add as many typical wa-lolita fails into it as I possibly could. Wearing protective eye gear such as a paper bag over the head is warmly recommended before reading on. In case of emergency refer to your nearest spork.
1. Random Japanese accessories such as a fan, paper umbrella etc.
These are a little bit yes/no when it comes to wa-lolita. Technically speaking they can look passable and good, but only when added to an already well put together outfit. If the coord fails no amount of randomly sprinkled-on Japanese items are going to save it, especially if they don't even match the outfit in colour/pattern/anything.
If the thought even crosses your mind that you would include them to make the outfit "more Japanese", don't... they probably won't, and you should not have to make your outfit look "more Japanese" for any reason. If anything, you should always look to the other side of the style name and strive to make your outfit "more lolita" instead.
2. Too strong make-up/geisha face.
(Created here with the help of GIMP for lack of white face paint.) :D
Too strong make-up ruins almost any lolita outfit with perhaps the exception of the most dramatic gothic styles. Same applies for wa-lolita.
Geisha-face is a HUGE no. Do not, for various reasons. The lolita related reason is that it's just not applicable to the style - lolita is not a costume and should rather look like something you can wear as street clothes if there's no reason that calls for a costumized look instead. The geisha-related reason is that you're not one. I'm usually fairly relaxed about cultures influencing each other in terms of fashion, but I draw a strict line to wearing something that to begin with is not available to just anyone even within its own culture; not everyone can be a geiko/maiko in Japan. It takes a long time, dedication and rigorous training to become one, therefore "if you haven't earned it it's not yours to have".
(I can quickly think up only one way that white base make-up could ever be used in lolita, which is to use it in a hime-lolita coord that draws strong influence on rococo era. Even then it's best to be careful with it.)
3. Zero effort on hair.
Leaving your hair open tends to fail unless your hair is unusually beautiful - but you will see that even lolitas with such hair style it carefully. A hairdo that looks effortless to make may in fact take a long time to accomplish. At the bare minimum at least keep it clean... it's also a good idea to avoid random hair accessories because if they don't fit the style in general they'll instead draw attention to the lack of styling.
What I would suggest instead is that you either style it in a typical lolita-applicable way or wear a wig. Contrary to popular belief (or popular as it regularly shows up in my blog stats as google searches) there is no specific wa-lolita hairstyle, but there are plenty of cute lolita hairstyles you should try instead.
4. Trying to wear it "sexy".
To repeat once again: lolita is a modest style. Wa-lolita is no exception.
If anything, wa-lolita should rank among the most modest of the lolita styles due to its yukata influence. It's never a good idea to let it hang off the shoulders, or wear a mini length skirt. You should avoid all attention to your boobs (I wear bras that flatten me up top for both wa-lolita and yukata/kimono wearing) because the ideal body shape in traditional Japanese fashion looks more or less like a tube.
This is possibly the biggest and for some reason also the most common wa-lolita failure there is. Avoid this and you're definitely on the right course.
5. A garish combination of colours/patterns.
You can have the most beautiful wa-lolita items ever in your closet but how you match them can still make a huge difference. Even when wearing kimono the colour combinations that can look random or non-matching actually are thoroughly thought about, well-planned and have a logic in them that makes the kitsuke balanced and not too busy.
If this sounds a bit harsh, like you're expected to fully understand Japanese aesthetics before venturing into the style, don't worry, no one's expecting that of you. Wa-lolita style is a lolita style in this part as well: matching the outfit's colours like you would match any lolita outfit's colours is the way to go and may even look better when the whole coord is put together.
6. Awkward, pseudo-Japanese pose.
This is more of a weeabooish photo fail, but as it can make a cute outfit look bad it's worth putting here on this list. Just pose normally instead of trying for anime-esque/theatrical poses or the ones that Japanese teen idols do; the first ones are exaggerated beyond belief and the second ones know what they're doing. Btw bonus points to anyone who can tell what stereotypical posture I'm going for here (hint, it's kind of gory)(and you'll usually see it with the head to one side).
7. What shall we do with our feet.
Another difficult part of wa-lolita is the stuff that happens below all that safely yukata/lolita going on above. Knee socks can look out of place, same goes for ankle socks. Bare legs look almost invariably bad in lolita with some rare exceptions. Shoes or geta/zori?
Many of this depends on the rest of the outfit, but here are some tips:
- tights are always a safe option
- there's absolutely no rule against wearing Western shoes, geta and zori can be too thin-bottomed to properly complement the rest of the look
- avoid formal attire items; even though the pics may be too small to see my zori are rather fancy, which makes them insta-clash with the informality of a street style
- thick, clunky bottomed shoes are often ideal since they balance out the outfit
- whatever looks the best by lolita standards is the way to go when it comes to this part of the coord
8. Lack of obi/accentuating your waist.
This is another very common mistake. Look at the part 2. for some examples of how you can still look very much lolita even though your boobs and waist are not on show.
9. Background of the photo.
This is another photo mistake rather than coord mistake, but a bleak/messy/dirty background to your photos will accentuate every bad thing in your outfit. You don't need a rococo castle to be your backdrop, the inside of your own room will do as long as said room is tidy and clean. Or the outside of your house, a street with a nice view, a garden.
Here for the final comparison are two very different approaches to coording a wa-lolita outfit.