first | or ! determine the direction of the stem. | is up ! is down.
once we know that, the symbols are written before or after the stem direction relative to how it appears in the actual glyph.
For example is we have
then obviously it will be written on both sides as "(|)" but if we have 
then it will appear only on the righ side as "|(". Quick chart guide:
and 
= "(" See how the glyph curves in a concave manner? Well, so do our parenthesis! 
and 
= "/" and "\" LOOK AT THE SYMBOL AND IT WILL BASICALLY TELL YOU HOW TO WRITE IT 
and 
= ")" Convex = convex parenthesis 
and 
= "/ /" and "\ \" 
and 
= "/ x )" and "\ x )" the x represents the stem direction marking. As you can see if you look at the symbol, it's a combination of ")" and "\ or /" and 
just have parenthesis on both sides. 
and 
are just like and but the arrow heads are reversed so the parenthesis and slashes will also be. They are "( x \" and "( x /" So once you get a grip of the pattern, writing these is really easy. You just have to remember which the ! and | and which sign represents which arrow head.