Photoshop eraser tool

[deaksy]

Hi. Could anyone tell me the best way to make this style for a T-Shirt on photoshop. I've tried a number of ways with the eraser tool byt can't get it like this. Also, tried making a pattern layer but again it didn't look good. 

Image attached!

Thanks

[pixxxelschubser]

This is most likely a hand-drawn pattern. You can draw it with a brush with about 75% opacity in the multiply mode. However, you have to paint in a layer mask.
And painting with a mouse requires some skill (or a graphic tablet and skill).

Here's a simple example (layer hierarchy and brush settings) - but quick and dirty drawn:

[c.pfaffenbichler]

What are you really trying to do here? 

How is this detail connected to the complete design? 

Please post meaningful screenshots or sketches. 

[c.pfaffenbichler]

What are the important elements in the illustration anyway? 

The more or less equally sized individual dabs at the lower end (red) or the squiggly lines in the lower upper half (green)? 

Translating an existing image into either in an efficient/automated manner might be challenging in itself.