Hi Hope,
The unhelpful but true response is that everyone is different and everything is different at different times! I suggest reading the sticky post "Diagnosis, treatment, etc." with all the introductions as most people describe their symptoms there.
My personal history to date: I had double vision episodes frequently the past 4ish years, with some episodes of arm and hand weakness lasting several weeks. One episode of weak jaw muscles impacting chewing during a meal.
I went to the urgent care in February with ptosis, where I was evaluated by a neurologist and neuro-opthamologist and given a tentative diagnosis with a Rx for prednisone (at the time, neuro didn't listen to me "remembering" bouts of arm weakness and thought I was only ocular or very very mild, so he thought prednisone would work). Prednisone helped for about a month and a half, then periodic weakness and fatigue symptoms started creeping back in - mainly in my arms and jaw and mild ptosis of my right eye.
Had a big exacerbation that sent me to the hospital 4.5 weeks ago and forced me to have plasma exchange: I had had a couple of days of lying in bed with leaden arms, weak neck and face, and slight labored breathing. The day I woke up feeling better, I pushed myself too much and had symptoms that mimicked either a pulmonary embolism or heart attack (rapid heart rate - for a long time - cold sweat and shortness of breath), and got admitted to the hospital from the ER when I made sure the attending doctor knew I had MG and he should get in contact with my neuro and the neuro on call at the hospital.
3 weeks on and I am getting symptomatic again and it's things I didn't really have that often before - weak face and slightly labored breathing. So you see it can change and fluctuate within one person as well as different people having different symptoms.