As Muse activity increases in the efforts to slow the Fading of Dream, Muses will naturally become more adept with their powers as they exercise them. On every odd-numbered turnsheet you will have one Skill point to spend as you wish on the next level of a Skill you already have (e.g. Strife Moderate → Strife Strong), or to gain a Skill you do not have (e.g. Strife Unskilled → Strife Weak). Skills cannot be raised beyond the maximum level of Exceptional.
You make this choice as part of your turnsheet on advancement weeks. Skill levels purchased in this way will take effect from the start of the following turnsheet (i.e. a Skill purchased on turnsheet 3 will only be available from turnsheet 4).
There must be a reason for your increase in power, though you may choose to explain your improvement however you wish in character - from simply becoming more adept from practice, to having a sudden epiphany in applications of Sculpt, or studying under a mentor.
You cannot purchase Quirks or Flaws as part of character advancement. These can, however, be gained or lost as the result of actions your character takes in game. You may also add or remove Playstyle Quirks freely and at any time - simply make a note at the bottom of your turnsheet, or send an email directly to the GMs.