How do I know how and when to apply a certain sifat to a letter in a particular verse since one letter can have up to five sifat?

Question
How do I know how and when to apply a certain sifat to a letter in a particular verse since one letter can have up to five sifat?

Answer
All letters have at least five characteristics (if we include the opposite pair of  and ) which are the characteristics which have opposites-meaning a letter has either one but not both of the pairs,   and the maximum is seven characteristics.  Any number of characteristics over five for a letter means the letter has special characteristics without opposites.  So with the pairs of opposites every letter has either or , for example,  because they are a pair of opposites, and a letter has either one or the other. 

We apply all the sifaat of each letter every time we read that letter, as it is a natural part of that letter and what makes that letter sound different than other letters sharing the same articulation point, or similar articulation point. The sifaat are clearer to the reader and listening when the letter is saakin (un voweled) but the sifaat are always present. 

Please see:
http://www.abouttajweed.com/the-characteristics-of-the-arabic-letters/the-characteristics-of-the-letters-p.html