diff --git a/README.md b/README.md
index 8accbdc1..e49ea904 100644
--- a/README.md
+++ b/README.md
@@ -11,19 +11,21 @@ as ES6. The JS and SCSS files are compiled and minified with webpack.
 This theme requires [Drupal 9](https://www.drupal.org/project/drupal/releases/9.0.0), [recommended PHP version](https://www.drupal.org/docs/system-requirements/php-requirements) and at least [Gin theme 8.x-3.0-beta2]().
 
 Requirements for developing:
-- [NodeJS ( 16.15.0 )](https://nodejs.org/en/)
+- [NodeJS](https://nodejs.org/en/)
 - [NPM](https://npmjs.com/)
+- optional [NVM](https://github.com/nvm-sh/nvm)
 
 ## Commands
 
 | Command       | Description                                                                       |
-| ------------- | --------------------------------------------------------------------------------- |
+|---------------|-----------------------------------------------------------------------------------|
 | nvm use       | Uses correct Node version chosen for the theme compiler.                          |
 | npm i         | Install dependencies and link local packages.                                     |
-| npm run dev   | Compile styles for development environment. and watch file changes.               |
+| npm ci        | Install a project with a clean slate. Use especially in travis like environments. |
+| npm run dev   | Compile styles and js for development environment. and watch file changes.        |
 | npm run build | Build packages for production. Minify CSS/JS.                                     |
 
-Setup the developing environment by running
+Set up the developing environment by running
 
     nvm use
     npm i
@@ -32,22 +34,105 @@ Explanations for commands.
 - `nvm use` : Install and use the correct version of Node.
 - `npm i` : As stated above; Install dependencies and link local packages.
 
+Related files.
+- `.nvmrc` : Defines the node version used to compile the theme.
+- `package.json and package-lock.json` : Defines the node modules and scripts for compiling the theme.
+- `postcss.config.js and postcss.plugins.js` : Configurations for the postcss-tool that is run when the theme is built.
+  You can read more about the tool here: https://postcss.org/
+- `webpack.config.js` : Configuration file for the webpack-tool that is used to actually build the theme. Similar tool
+  to Gulp or Grunt. Usually if there is something wrong with the compiled theme files the culprit can be found here.
+
 ## Structure for files and folders
 
+### The config-folder
+
+The config folder includes configurations that are used when installing a new project from scratch. These configuration
+files are copied under the `conf/cmi` folder and used there. Therefore, altering them under the theme doesn't change
+anything unless you are building a new instance.
+
+### The dist- and src-folders
+
+Under the `./src` folder, there are all the theme components that are being compiled to the `./dist` folder, such as
+CSS, JavaScript, icons, and fonts. The `./dist` folder includes the compiled version of the same information created
+using the commands listed under the commands title.
+
+The theme styles under the `./scss` folder are structured by implementing principles from the ITCSS architecture but
+with small adjustments to make it work for the needs of the project.
+
+### Templates-folder
+
+Under the `./templates` folder, the structure is similar to the base-theme stable9 with a few additions, such as the
+`./templates/module` folder that includes templates for the helfi-prefixed modules created for this project.
+
+### Translations-folder
+
+The `./translations` folder includes translations for all the translatable strings provided by the hdbt-theme.
+
+## Webpack entries
+
+Any .js file in /src/js/ will be compiled to separate entry and minified into the /dist folder.
+Typescript entrypoints must be added separately. See webpack.config.js.
+
+### How to use entries in Drupal libraries
+
+Example:
+```
+component-library:
+  version: 1.x
+  css:
+    theme:
+      dist/css/component-library.min.css: {}
+  js:
+    dist/js/component-library.min.js: {}
+```
+
+Library must be loaded on the page where it's used. It can be added via preprocess function or in a twig template. Read
+more about using libraries in Drupal from for example from
+[here](https://www.drupal.org/docs/develop/creating-modules/adding-assets-css-js-to-a-drupal-module-via-librariesyml).
+
+## How tos
+
+### How can I add custom translations?
+Add your UI translations to `./translations/{fi/sv}.po` files like it is explained in Translation in Drupal
+documentation: https://www.drupal.org/docs/understanding-drupal/translation-in-drupal-8.
+These translations consists of:
+
+PHP
+```
+$this->t('Example', [], ['context' => 'My custom context'])
+```
+Twig
+```
+{{ 'Example'|t({}, {'context': 'My custom context'}) }}
+```
+JS
+```
+const variable = Drupal.t('Example', {}, {context: 'My custom context'});
+```
+
+And the way to add the actual translation in to f.e. `fi.po` is done like so:
+```
+msgctxt "My custom context"
+msgid "Example"
+msgstr "Esimerkki"
+```
+
+To see these translation changes in an instance, run in container shell:
+```
+drush locale:check && drush locale:update && drush cr
+```
+And then flush all caches from top left drupal admin menu under "Druplicon".
+
+### I have some php linter errors
+
+You can lint or fix php in instance root's shell
+
+To lint
+```
+vendor/bin/phpcs public/themes/contrib/hdbt_admin --extensions=php,module,theme,inc --ignore="*.js,*.css" --standard=Drupal
+```
+
+To fix
 ```
-hdbt
-│   README.md
-└───src
-│   └───scss
-│   │   │   styles.scss
-│   └───js
-│   │   │   common.js
-│   └───icons
-│       |   sprite.svg
-│       └───subdir
-│           |   some-icon.svg
-└───dist
-    └───css
-    └───js
-    └───icons
+vendor/bin/phpcbf public/themes/contrib/hdbt_admin --extensions=php,module,theme,inc --ignore="*.js,*.css" --standard=Drupal
 ```