There are times when splash racking can actually benefit your wine. It can rid your wine of odors and or gasses commonly associated with wine making such as sulfite or sulfur to name a few. Splash racking can also aide in the degassing of a wine.
Care must be taken to not do more damage when slash racking. Proper sulfite levels must be maintained to ensure oxidation does not occur to your wine. Typically reds can benefit from a splash racking while whites can tolerate it once.
To splash rack place a sanitized funnel in the neck of your carboy. Carefully pour your wine thru the funnel taking care not to overflo the funnel. I use a screen in the funnel to catch any leftover pieces of fruit from entering the carboy.
If you are going to be fining your wine at this time fill the carboy to the shoulders first with wine, then add your fining material.
Stir completely (this will help to degass and mix the fining agent) then replace the funnel and top off your carboy with more wine, then with an airlock and bung. If you are going to be adding any other ingredients such as potassium metabisulfite or potassium sorbate I like to add them prior to splash racking to incorporate the ingredients into the wine.
If you are attempting to rid your wine of any unwanted odors such as sulfur or others, check your wine a few days or weeks after splash racking to see if it has worked.
P.S. The carboy in the photos is in a 6 gallon bucket due to a deep scratch on the outside of the carboy. Carefully review any used carboys prior to purchasing.