Various multicolor writing tools and methods for applying multiple volatile marking substances one at a time. The tool includes a case member, a cartridge member, a cap member, and an optional actuator member. The case member forms an interior in which is disposed the cartridge member with multiple cartridges each containing one of the marking substances and a tip through which the marking substance is applied. The cap member changes and restores its configuration, while the actuator member changes, the configuration and exposes one of the tips selected by an user out of the interior when the tool is in use, and then restores the configuration and encloses all of the tips inside the interior when not in use. Thus, the tool opens the cap member in response to input force without requiring the user to engage in a separate maneuver to remove the cap member.