Okay, I understand the principles of sub-dividing, but I seem to have trouble actually apllying it while playing.

Is there any sort of practice I can do to get my sub-dividing skills up?

I have 2 teachers and I'll ask them. But I was just wondering if there are any excersises on the internet.

I'm sightreading a lot now and I am actualy sub-dividing now quite alright.

It's is all just subdividing.
I do not think you are doing anything 'wrong' you are just not going full circle.

When I see this type of issue with my students I find that mostly they are thinking 16th and 32nd notes are FAST!! Well, yes they can be but two 8th notes = a quarter. Two 16th notes equal an 8th. Two 32nds = a 16th.

My suggestion is you go back and relearn or retrain your brain thinking process. Do this 3 step exercise.
Step one :
Take out your music, find the shortest note duration. If it is 16th notes, then start at the begining of the piece and play constant 16th notes. So, if the piece starts out quarter, quarter, 8th, 8th, 16th, 16th. You will play 4 16ths for the first note and second note, 2 16ths for the 8ths, and of course 16ths for each 16th.

Step two:
Again play the piece playing constant 16ths notes. But htis time accent the beging of the written notes.

Step three:
Play the piece feeling the 16th notes, but play the notes as written. You should feel the 16th notes somewher ein your body (don't beat your foot though).

Give it a try.