Six Secrets to Keep your Clothes Stain Free!

First - NEVER, EVER, RUB A STAIN OR SPILL 

Rubbing stains, grinds soils into the fibers of your garment AND because rubbing acts like sand paper, rubbing will likely cut fibers in your garment and cause 1) de-lustering (which looks like a stain, but is actually fabric damage because the material is no longer reflecting light like the rest of the garment) and/or 2) it can cause color loss.  I know its hard, but please refrain from rubbing any stain or spill if you want to prolong the life of your garment.  This is especially true of silks and satins.  AND alcohol can easily remove the dyes from silk items - so BOT, BLOT, BLOT until your beverage stain is gone!

TIP: Men, take off your tie before eating. Or at least throw it over your shoulder!
Another TIP: NEVER put water (including club soda) on a silk anything to remove a spill.  It will make it harder for your drycleaner to fix the garment in the end!  

The best thing you can do any time you spill anything on your clothes is to BLOT up the excess soil/liquid with a clean, lint-free, light colored cloth

Second - treat your stains promptly

Mom was right (isn't she always?). Fresh stains are easier and more likely to be removed.  Less well known is the physical and chemical damage that can be done by leaving stains in your clothes.  When some stains (alcohol, sugar water and perspiration to name a few) are left in clothes they can weaken fibers causing your garments more likely to tear, or start holes.  The can also cause a chemical reaction that damages the dyes causing color loss.  Also, soils left in clothes will attract insects which, besides being gross, will eat holes in your clothes and then destroy any wool items in your closet. 
Also keep in mind, that if its hot, or you leave soiled garments in a car, the heat will effectively cook your clothes and set stains in a matter of 15 minutes!  Another reason you should find a cleaner that picks up and delivers!

Third - If your item is Dryclean Only - take it to your drycleaner and ignore the rest of this post

If you have a silk blouse or acetate dress or any other item with a "DryClean Only" care label, STOP HERE and take your items to your favorite drycleaner.  You will know if your item is dryclean only if there is a circle symbol on the care label like this

Disclaimer: The following information is ONLY for items that can be safely laundered

Fourth - Carry a stain stick with you  

Like the third rule says, treat you stains promptly.  Carry a stain stick in your purse, and your car. They are cheap and easy to tuck into your purse, glovebox or desk.  I personally like the Clorox and Tide sticks the best.

Fifth - work the stain from the "wrong side"

If you are going to "work" a stain before you put it into the laundry, use this drycleaner trick; Flush the stain from the backside first.  Its easier to "push" the stain off the surface of material, rather than force it to travel through the material. Another way to say this is to "lift" the stain off the material.

Lastly - For greasy stains

For a lot of grease (pizza anyone?) put a little dishwashing detergent in with your load.  Be sure the water is already filling your basket,  You want the water and detergent to mix (dilute) before adding your clothes.  You may apply this de-greaser directly to clothes, but FIRST you will need to dilute it considerably with water.  I love Dawn, however I would never apply a colored anything to clothes directly.  I always dilute any product with water before adding clothes.

As for specific stain removal tips (mustard, grass, etc.), I ran across this fabulous article by the University of Nebraska:  http://lancaster.unl.edu/home/articles/2002/summerstain.shtml.
It was written in 2002, but the tips are as true today as they were then.
As a drycleaner, because I have access to all sorts of stain removal chemicals the average person cannot get, I did not try these stain removal techniques, and their effectiveness is up to you to determine.  I would love to hear your favorite home stain removal techniques!