If this is your weapon:
It's a revolver -much easier to clean than a semi-auto.
Find a shop near you that sells Slip 2000:
Find a Dealer
It'll likely be at a shooting supply shop or a shooting range. While there, get a cleaning kit with a brass brush for a .38 or .357 -either will work. Also, get some cloth cleaning patches.
First, check for any flat screw heads on your weapon, and if they're loose, make them hand tight before continuing.
Keeping your finger off of the trigger, open the cylinder where the six cartridges go. It should rotate to the left of the frame while pointing the barrel away from you. Make sure that there's nothing in all six.
Take the brass brush and run it through all six cylinders and the barrel.
Then, take a cloth patch and run those through the same until the cloth comes out clean.
Take some wooden toothpicks and put a bit of the Slip 2000 on one end. Run the moist end at any point of the weapon where metal rubs against metal (The hammer, the cylinder central post where it spins, the trigger linkage, etc.)
Then, put a dab of Slip 2000 on one of the cloth patches and run it once through the same areas that you ran the brass brush -the cylinder and barrel.
Work the trigger, hammer, cylinder release pin over and over until the movements seem smoother to you.
Wipe off all excess oil as well as the entire weapon.
All you should have left to do is to get some .38 ammo and fire the thing. Just load a single cartridge first to get used to how it'll handle in your hands. When you've finished, clean it again to clean up all of the crud that should have shaken loose from the weapon's firing.
I'm just going off of how I clean my .44 Magnum revolver, but you can find a LOT of YouTube videos about how to clean a revolver (Or any other weapon)
I like Hickok45's videos the best, though.
Best of luck, and I hope this helped.