First two guesses were vowel hunting. For guess 3I was left with three possible roots: xxAxx (such as STAMP), AxAxx (such as AMASS), or xxAxA (such as DRAMA).
I decided there were more options in the xxAxx path so I decided to go that route in guess 3. I opted for STAMP because it tested for S and T, both common consonants, and included a M, which could help with DRAMA and AMASS if the root wasn't xxAxx.
After guess 3 I figured the M was most likely in position 5, which seemed to limit the possibilities to xxARM and xxASM. xxARM had more open options than xxASM. With remaining letters, I thought CHARM was a good guess.