Briefly...
-Round circle things are for left and right temperature. You have to push the snow flake button to turn the air cond on.
-Blue & red dial controls the temperature from only the dash vents (except when others mentioned above are set to maximum cooling).
-Memo buttom is a time reminder. It will sound every hour on the hour if activated. Limit button is a speed warning. It will sound if you exceed the the maximum speed you have entered.
-Security light is supposed to flash for 36 hours after shut down if you have the anti theft system activated.
-The A/M button by the shifter is for the trans mode you desire. In "A" the trans works like an automatic normally does. In "M", the trans will stay in the gear you select with the shift lever.
-If you have a tilt wheel, there will be a lever under the steering column. Few 3 series in your year range have tilt wheels.
Buy a manual ASAP, you'll be very glad you did.
HTH