Advancement
After your character has gone on an adventure or two, they might take some time during Sojourn mode to go through
To increase a Skill, it costs a number of XP equal to the new desired Rank of the Skill. For instance, if your Training Rank in Healing was 3 (Proficient) and you wanted to increase it to 4 (Expert), it would cost you 4 XP to increase it.
It costs twice as much XP to increase a Reserve or Resistance. The following tables can be used to quickly discern how much XP is required to increase your Training Ranks. The Total column lists the total amount of XP required for the desired rank (starting from Rank 0) and can be quite useful for the development phase of character creation.

Normally, during an Advancement, you can only increase the Training Rank for any Skill, Resistance or Reserve by one Rank. The exception to this rule is during the development stage of character creation. The GM might also allow increasing by more than one Rank if your game is using the optional training rules and your character is spending a particularly long time working with a trainer or mentor.