Adding Detail??

I am working on a War Of The Worlds Tripod and something I am doing bad on other than the legs is the detail all around. This is going to be a game model so i have to keep it kinda Low Poly. But ill talk about the head for instance, the picture I am looking at has antennas on the head with little shapes sticking out. The head on my model doesnt have any detail at all. How would I go about modeling that small detail?

My model: https://gyazo.com/0b859d17b68a086dd70179037cac9c47

Actual movie model: https://www.google.com/search?hl=en&site=imghp&tbm=isch&source=hp&biw=1366&bih=662&q=war+of+the+worlds+tripod&oq=war+of+the&gs_l=img.1.2.0l10.1030.3039.0.4262.13.8.2.3.3.0.177.688.5j2.7.0…0…1ac.1.64.img…1.12.699.0…35i39k1.vQ3zwdv2rjo#hl=en&tbm=isch&q=war+of+the+worlds+tripod+head&imgrc=3VXOgEci2cOMNM:

you model the basic shape and then use UV mapping + texture painting to paint a normals map. UV mapping is a way of precisely painting textures, and normals mapping is a way to fake depth and detail using a texture instead of polygons.