Hello, annem. 
1. Problems with “t” single or part of consonant cluster
Chinese has an unaspirated < t >, whereas English has an slightly aspirated < t >. Have your student hold up a piece of paper in front of her/his mouth while pronuncing tan, ten, tin, ton - releasing a puff of air after < t >; the paper should move.
For consonant clusters, say st, try this:
write the letter s on the right-hand side of the board or piece of paper;
write the letter t on the left-hand side,
point to s, have the student pronounce the sound,
point to t, have the student pronounce the souond,
do it again, this time gradually speeding up the processes until the cluster st comes together.
Alternate: use your hands, right for s, left for t, slowly and gradually bringing them together.
2. Problems with “l” and “r”
Here's one to add to tdol's twister: Laurie likes rice,
Rory likes lice.
Note, Rory is a cricket.
3. Problems with schwa sound at end of words
That's a very common error among Chinese speakers of English. Try the paper trick once again, this time using word-final consonants; e.g., nat, nad.
(Note, the example words do not have to be known or 'real' words. The trick to finding the right examples is to choose words the majority of sounds of which your student can pronounce quite easily.) Here's what to do:With final voiceless-consonants (like 'nat') have the student switch her/his final schwa with final aspiration (a puff of air).
With final voiced-consonants (like 'nad') have the student practise stopping the release of final [d]. Like this, form /d/ by placing your tongue on your alveolar ridge, get ready to say [d], but don't say it, now stop. That's an unrealed /d/, and learning how to do that will help your student gradually stop feeling the need to add schwa at the end of words.

Originally Posted by
annem Can you recommend any strategies, activities, techniques etc for me to use to help this student?
1) Tape record a few sentences or a short paragraph and listen to the playback for errors.
2) Work on word stress and sentence stress. You'll definitely hear quicker results.
3) Sing songs. It's one of the best ways to improve one's pronunciation - in any language.
All the best.