Actually, since you do not seem to have too many scars and they are localized, you should use a 1.5 mm dermastamp and the single needles (use the single needles on ice pick scars.).
Stamp the same scar 6-8 times in one go with the dermastamp. If it heals OK you can stamp slightly more the next time. You have to experiment a little.
You can stamp or needle whenever you have time but do not stamp or needle the same scar more than once every four weeks.
The area around the mouth is from my experience the most sensitive and you might need a numbing cream there. You can buy it later, after you tried it without one.
Whenever I receive a question about scars on the nose, I get nervous.. The problem is, that the skin on the nose reacts very unpredictably comparing to the rest of the skin. Nasal skin can heal worse than you started with. There is no fat layer under that skin, there is only cartilage and that might be the reason.
I can only suggest this: Use the single needle on it but do not do any aggressive needling. Concerning the nose, ignore the guidelines for needling that are on our website. Make just three pricks into your scar (to the bottom of the scar not to the edges).
If it heals well, make four pricks the next time. If it heals well, make five pricks the next time. Continue like this but never do aggressive, dense needling. Just a few, very gentle pricks.