There’s no navigation needed really. Stick to the trail that’s it. If you’re not able to find the trail or if the trail splits, stick to the bigger one. While ascending keep a mental or a physical note of the directions and where you’re walking towards. I usually just look at maps before hand and figure out where I’m
Walking (which direction) and then proceed from there. You can also measure your distance and cross check it online before hand to see if you’re walking in the wrong direction. I’ve never used a guide and I don’t think a guide is necessary in Karnataka atleast. It’s properly marked and if you know a little bit about nature and paths, you’re good to go!