This is the audio exerpt of ɜː spoken within a word. It may sound a little short or unclear, but that's exactly how it's in the real context. For more details, read the below explanation of pronunciation and listen example words that contain ɜː by pressing the word buttons.
1. Open your mouth for about 60%.
2. Relax your lips.
3. Raise the center of your tongue without touching the palate.
4. Push air from lungs while vibrating vocal cords.
5. Pronounce this sound noticeably longer than normal ones.