Open config.cfg with a text editor (like Notepad) and adjust the following settings for a good starting point:
// Graphics Settings r_mode -1 // Use this to adjust your resolution, e.g., r_mode 16 for 1024x768 vid_restart 1 // Apply graphics changes fps_max 100 // Cap your FPS to 100
// Crosshair Settings crosshair 1 crosshair_size 1 crosshair_thickness 0 crosshair_outlined 0 crosshair_drawoutline 0 cl_crosshaircolor 5 // Custom color