1. Choose where you want the line to being and position the pen pointer there. 
Click the pointer to set the first anchor point. 
This point should stay solid until you set the next point.

2. Click again where you want the first segment to end. 
You can also use Shift+click together to move the angle of the line in multiples of 45 degrees.

3. Continue clicking to set more anchor points for more line.The last point is always a square.This shows you that it's selected. 
As you add more anchor points, previous points will become hollow inside.

4.You can click to remove an existing point if the Auto Add/Delete has already been selected selected.-There, see how easy it is once you know how!
 
 
 
 
 

Each of these filters takes a single click to apply. You can find lots of free filters on the net  (even more to buy if you must) please see our resources page for both kinds
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"Filter Finger", (too much clicking in the filter list) is an occupational hazard peculiar to designers and a syndrome akin to the child with a new toy that comes with lots of accesories and who must investigate every possible combination.  Some really obsessed artsy types can't stop until they have tried every known combination of filters in Photoshop because they are afraid they will have missed the "perfect" visula effect for whatever project got them to venture into the filter list in the first place. It's a great place to play but you really wouldn't want to spend more than a few hours there unless you don't mind crampled fingers and other parts.

Each of the filter effects above was a one filter shot. However, you could add one filter and then add another and another etc., so the mathematical possibilities are pretty awesome. Using the same filters in a different order will get you a get a very different effect. Many times it's impossible to get the same effect twice because you forget the sequence - oh well, next time I'll write 'em down.