Basically the title contains the entire question. I learned music as a kid in Ukraine. In Eastern Europe (ex-USSR), commonly used note naming is "Do-Re-Mi-Fa-Sol-La-Si" ("fixed do solfège"), not the germanic "C-D-E-F-G-A-B". Nowadays, I have no trouble reading music, I instantly recognize the notes, but I'm constantly stuck if I need to pronounce them aloud in English. Is there a good technique to "retrain myself" into thinking in English notation after I've already ingrained a different one a long time ago? Did anyone here had a similar experience?
It seems to me the process of relearning the names of the notes is akin to learning to speak a new language - but fortunately you only have to learn a small number of words.
Perhaps flash cards - one with Do on one side and C on the other, another card with Re on one side D on the other and so on. Shuffle the deck and just pull out a card and say what's on the other side. Quickly check your "guess" by turning over the card. Do it both ways (guess the letter name or the solfège name while looking at the other). Eventually you will have them all memorized and will be able to instantly say E when you draw the Mi card or say F when you draw the Fa card.
The "Do-Re-Mi-Fa-Sol-La-Ti" pattern refers to the scale degrees in a scale, these are not representative of specific notes until you specify which key this is in. For example...
In the case of C Major: "Sol" is the G note.
But in the case of D Major: "Sol" is the A note.
So for each of the 12 different major scales the solfège "Do-Re-Mi-Fa-Sol-La-Ti" pattern will represent different notes. We do use solfège here in the US and I learned it as a kid as well, but solfège is different from the actual notes.
If it helps you can apply the solfège pattern to the actual notes. If you're in the key of C Major, then C=Do, D=Re, E=Mi, etc. and you can think of it mentally this way. The more familiar you are with each of the 12 keys the easier this will be and all you can really do here just practice. The more time you spend working on it the better and faster you will get at it.
It's a shame that the people you're trying to communicate don't understand you. I've seen adult musicians brought up in Latin America use do-re-mi in the U.S. and be reasonably well understood by people brought up with C-D-E....
With any memorization task, the more difficult one finds it, the greater the need for a mnemonic. I will propose something for you -- but please don't hesitate to modify it.
For reference, here again is the equivalence chart:
The easy ones are
Mi - E because they rhyme
Fa - F because they start with the same letter.
Here are some suggestions for the others:
D: reD (the color)
G: God (think of the sun god)
A: Ah (The doctor says, "Stick out your tongue and say 'Ah'." 'Ah' rhymes with la.)
B: If you are a Spanish speaker, perhaps you could use this: tiBia. If you on the leading tone, almost up to tonic, you are lukewarm, in other words, you are heating up some water and it is almost hot. (For non-Spanish speakers, I'll explain that tibia means warm but not hot.)
A fun exercise might be to try to sing "Do, a deer" (from The Sound of Music) with the C-D-E method:
C, a deer, a female deer,
D, a drop of golden sun,