RRM - Relatively Realistic Mountains using Photoshop

[Zaramis]

To answer your questions:

1) - I meant the layer style.

2) - It's correct that you should use a brush of just 1 pixel. If you don't want that subtle a result at first, you can use 50% flow and opacity just to experiment with it - with such high amounts, you should immediately see how mountains appear whenever you paint a single pixel worth of color. If you use even more, or use a bigger brush, it gets a too heavy an effect - which is most likely the reason why your mountains glomp together, most likely - by using a single pixel with such a low flow, you paint the same area multiple times to create the different height of mountains. Make sure you don't have "Chisel hard" but "chisel soft" as well, on the layer style.

3) - I use the brush, not the stamp tool. The entire pattern which gives the mountains their color is made in the earlier step, the mountains are just single pixels that are embossed heavily to create the idea of a mountain - if you paint small black pixels on a green fields, the black pixels won't actually be seen but the "mountains" around them will be.