Notepad++

[Daemian]

4. Download userdefinelang.zip, unzip and go to Language - Define your dialogue → Import unzipped file “userDefineLang.XML”

It says you gotta download the file UserDefineLang.zip (click it), then you unzip it anywhere like c:/doom. You get a file called userDefineLang.XML.
c:/doom/userDefineLang.XML This one you import it as a new language into Note++. How you import it?
Open Notepad++, go to the menu Language (next to Encoding), from the list you click Define your language. This opens a new window to customize/define a new language. Click the button "Import..." (the one at the left-top corner). Now you select the file you just downloaded c:/doom/userDefineLang.XML. Accept and you're done.

5. Download hps.zip, unzip and go to Program Files\Notepad++\plugins\APIs and put hps.xml here.

This step only wants you to place a file (hps.xml) at /plugins/APIs.
So, download the file by clicking it (not here, on the wiki), unzip it, move hps.xml to /plugins/api, and restart notepad++.

If you can't locate this directory, you can press the Windows key, type notepad++, right click it from the list and select Open file location.
Now enter the directory plugins/APIs. There you put the file. That's all.

Just so you know, you can make notepad++ treat any file as a .hps by going to Language menu -> click HPS at the bottom.