This technique requires minimal preparation, but it will help you zero in on the words/sounds that a student is struggling with. And it will enable you to help him/her improve their pronunciation in a non-threatening way.
(For simplicity of pronouns sake, we’ll use a male student as the example.)
1) Find something for him to read aloud. It can be an essay that s/he wrote or an article that you have found. You will need two copies of it: one for him and one for you.
2) He reads it silently for about one minute.
3) He reads that part aloud and records for about one minute. While he is reading aloud, on your copy of the passage, you circle words that are mispronounced or just not clear.
4) Together, you listen to the recording and stop at those circled words. Rewind a bit to let him hear what he read and compare it to your correct pronunciation and let him try to say it correctly.
5) After you have gone through that one-minute reading, you can review the circled words and/or have him re-read that part of the passage again.
6) Continue with another one minute of passage etc.
Option 7) He monologues for one minute about anything. (You may want to give him a topic). Record his monologue. Play it back and stop at mistaken places and work with those words.
If you don’t have a way to record, just circle the words while he reads. When he finishes, just read and repeat the circled words until he says them correctly.
During the next session with the student, it could be helpful to have him read the same passage aloud to see if he had internalized the correct pronunciation.