It really depends. I'm assuming you're relatively new to stick like me. I've just gotten a lot more comfortable with downshifting so I'm more likely now to get the appropriate gear WHEN i need it, instead of being a lower gear and higher RPM all the time.
I don't bother with 6th unless I'm cruising on the freeway or open roads with no traffic, since lot of in-town is around 45 MPH and 5th is perfect for it.
If I need some gitty up, 5th to 3rd is pretty easy and I'm good to go.
How is the terrain in your area? For example, you don't want to be in 5th when going up a hill at 30mph. You'll have no power and you're bogging the engine.
It's a balancing act that you'll adjust to if you become more aware of the car as you drive it. I'd recommend leaving the stereo off or having it on very low as you accustom yourself to what the car likes @ certain RPMS, @ certain speeds, on varying types of roads. You'll be able to hear and feel (as you press on the gas pedal) what your car needs you to do.
Part of the magic & fun of having a 6MT