Trumpet

Here is a video on cleaning your trumpet.  In the video they take the valves out of the trumpet and take them apart and then put them in water.  I suggest taking the valves out and cleaning them with a cloth (without taking them apart), and put the rest of the trumpet in water as shown in the video.  If your slides don't move, you may need to send your trumpet to the repair shop (check with your teacher first).

Trombone

Here is a video on cleaning your trombone.  In the video they use a shower to clean the instrument.  You could also use a bath tub to submerge your trombone.  If your tuning slide won't move, you may need to send your trombone to the repair shop (check with your teacher first).