How do I self-answer "What does this say?" We get a lot of translation requests at Chinese.SE, and while we'd like to help, there's sometimes very little about the Chinese language in the question, and a lot about the procedure for obtaining plaintext from a photo.

Once we have the plaintext, we can simply input the plaintext into e.g. Google Translate or Yabla to get an approximate answer.

The aim of this post is to develop a self-help guide for use as a duplicate target.  Instead of closing these questions as "off-topic" and linking to an impractically long list of (mostly inapplicable) resources, it'd be better to close as a duplicate of this self-help guide.

Question: How do I self-answer "What does this say?"

Answers:


Input the text into optical character recognition (OCR) software.
What about handwriting?
It's also possible to input characters by drawing them by hand.
We can also search for a character by radical.
Searching modern characters by any of their constituent components.
Searching archaic character forms by any of their constituent components.
What are some commonly encountered Chinese characters?


Still don't know?  Ask on Chinese.SE but please show prior effort.  For example, I asked this question: What does 我们已经帮您踩过了 mean in this peculiarly translated escalator sticker? and you can see what happened.

For things like seals, stamps, calligraphy, etc., it's sometimes impossible to get a translation without asking someone who can read Chinese (and sometimes even native Chinese speakers struggle with this).

There are Internet communities which welcome these questions: like Reddit's /r/translator (and /r/ChineseLanguage has a pinned 翻译 Translation Thread!).
Handwriting

TL;DR: Handwriting is much harder than printed text.  The first step is to improve the image quality.  Afterwards we can input the text into OCR software.

This is on a door where I'm staying.



If we put it directly into Online OCR, it says:


  No recognized text !


The image quality is too poor.

Step 1: Improve the image quality.

We can open up Paint (actually I use Pinta) and go over the Chinese in black.



Method 1: change the brightness and contrast:



Method 2: select only the black text (e.g. GIMP has Tools/Selection Tools/By Color Select):



Step 2: Input into OCR software.

OCR software struggles with handwriting, so we may need to try a few times.  If we input the second image above into Online OCR, we obtain:


  请各位出入
  头好蓝色水门 


It made two mistakes:


the original says 关好 (close) and not 头好 (meaningless);
the original says 木门 (timber door) and not 水门 (water gate).


So it's not perfect.

However, inputting the third image into EasyScreenOCR gives:


  请各位出入
  关好益包木门


It also made two errors:


the original says 蓝色 (blue) and not 益包 (meaningless).


Step 3: Compare the outputs; fix bugs.

We can compare these two transcriptions.  The writing is stuck on the inside of a blue wooden door, so...


关 (to close) makes sense and not 头 (head);
蓝色 (blue) makes sense;
木门 (timber door) makes sense.


So we can fix the bugs to obtain:


  请各位出入
  关好蓝色木门


(It may be useful here to search by radical to identify troublesome characters.)

Step 4: Translate.

Now we put this into Google Translate to give:


  Please come in and close the blue wooden door


Actually, it's not a very good translation (出入 means "come in and go out").  We can break this up a bit further using Yabla:



Thus it realistically means something like:


  Please, when coming in or going out, close the blue wooden door.