Photoshop : How To Dash Gap Stroke Styles Tutorial | Graphicxtras
Dash styles, dots / dash / gaps can be used with shape layers, any design can be used. Go to the custom shapes tool in the tools panel and select a preset from your set; or simply go to the ellipse tool and then create a circle (hold down the shift key to make it a circle) with the layer option (top left) in the control bar. With your vector layer, you can add a fill (such as a gradient) but you can also add a stroke.
Set the fill to white and the stroke to black and set the stroke width to 50, makes it a whole lot easier to see the steps. Go to the control bar next to the width entry and click the 'set shape stroke type' (or stroke options as it is called on the panel). The same can be found in the properties panel.
The panel displays some presets, you may like to try those but there are very few included by default.
On / Butt setting
With the Dashed line on, set the dash and gap. If you have set the width to 50 then if you go for a setting of 1 and 1 then you will have 50pt - 50 pt all the way around your design (the width is 50) if you use the butt, center, miter settings.
Round / Square
The round and square caps make it slightly harder to see the design (so stick with butt for this tutorial).
1-2 or 1-2, 3-1 etc for the entries
Go for a 1-2 then you have a 50pt - 100pt and if you go for 2-1 then it is a 100pt and 50pt gap and so on. There are also two other pairs to use so if you set it to 1-2-1-3 then you get 50pt with 100pt and then one entry of 50pt and 150pt spacing. So you can see you can create all kinds of different designs just by adding 1-2-1-2 etc or 4-3-2-4 etc.
Align - Outside, center etc
If you set the align to the outside then the stroke will suddenly be outside of the vector design, go for inside and it will be interior though the result depends heavily on the size of the design. The cap option is the thing that really varies the whole thing and you can still use the 1-1 etc with round and square but it is harder (I think) to see the relationship with the 1-1-2-1 settings etc.
I have been describing 1-1, 2-1, 1-1-2-1-3-1 etc but you can also use 0.2-1.3 as well as 2.5-1.2 etc, they can be decimals.
A few features are missing from Photoshop such as the option for phase, you cannot nudge the settings around the vector design, you get what you get.