Tengwar is a fictional writing system devised by J.R.R. Tolkien to support the rich history of Elves in Middle Earth. As Tolkien was an Englishman, there are several examples in his hand of English prose written using Tengwar.
In Tolkien's fictional world, the Tengwar gave written form to the Elvish tongues of Quenya and Sindarin. Tengwar could also be used to transliterate the tongue of Mordor, as it famously did in the case of the One Ring's inscription.
Since the Lord of the Rings movies were produced in the early 2000s, there has been an undercurrent trend of "elvish" tattoos of names or mottos. This is where I got started with my Tengwar fascination.
Here is how I spell my own name in Tengwar (rendered here with the Tengwar Annatar font):
Would I get a tattoo of that? No, I don't think I will.
As I began to learn more about Tengwar and the mechanics of the writing system, I was struck by its depth and beauty. Although I am not a linguist, and you likely aren't either, I would recommend The Tengwar Handbook by Arno Gourdol and Amanye Tenceli by Mäns Björkman as excellent primers on the most common ways to read and write Tengwar.
I began to journal (painfully slowly) in Tengwar, in an effort to learn it better. I tried to adopt the "English Mode" as described in the above resources.
To help myself out, I created a modest single-page reference for transliterating English to Tengwar. It was intended for my own personal use, but others may find it useful.
Download: Tengwar Reference PDF (139 KB)
I favor transliterating orthographically rather than phonemically (my brain just works that way), but the reference should be helpful to writers of either method.
For more information about Tengwar and related topics, see these excellent sources: