Do I have to cite myself? If yes, how?

If you cite yourself, it is the so-called auto-citation and it is a citation as any other citation. This issue is dealt with when it comes to scientific researchers, but the following rules are applied:

• Cite yourself whenever you use your older works (e.g. whenever you take over the results of your research you have published somewhere else)
• These citations are usually listed at the beginning of the In the References (in Harvard style and Footnotes)

Where you do not cite:

• If you still have not published the results anywhere else (e.g. you have not presented the results of a research in a seminar paper or a paper at a conference)
• When you present or use a text in a foreign language in your work (article, book, web), you are not listed as the translator of the text, but it is better to write a note, e.g. my own translation; author’s translation etc.