I guessing you are refering to the stroke of the text (the outline)

Well to achieve the text effect used in the signature you will need a 'pixel font'. Good examples of pixels fonts are Elektr_02_5 and NU.

Now, type the text you want using that font (note that pixel font's are only designed for a set font size (usually 10. NU: 9) but will usually work in one of it's multiples (20, 30, 40 etc). Also the do not work with Anti-Aliasing enabled on the text toolbar:


Make sure it is set to 'None'

So with the text typed, drag your curser over the the layers box,right-click on the text layer and select 'Blending Options'



Now you get a window with a whole load of effects options for that layer. Sect 'stroke' right at the bottem (note that it automatically applys that effect, but don't worry, blending effects can be turned on and off and be changed at any time)



So you are presented with two groups, one being the 'structure' group and the other being the 'fill type' group.

Firstly we are going to change the colour of the stroke to black. This is done by clicking the red box in the 'fill type' and then selecting black in the colour picker which pops up. Click ok to apply the colour.

Next we are going to change the stroke thickness to 1. This is done by dragging the 'size' slider in the 'structure group' to the left.



Now we are going to change the inner colour (to make the text readable).



Select the 'Color Overlay' option at the side and click the coloured box next to the 'blend mode' dropdown and choose white (or any other colour you think fits, I reccomend trying out some greys).

__________________