Participants will be asked to complete 7 brief online modules to cover how to understand emotion-triggered impulsivity, to better detect states of high emotion and arousal, to learn new strategies for self-calming high arousal, and to pre-plan how to cope with high arousal states. As part of the program, participants receive daily texts and prompts to remind them of the intervention content and skills. At baseline and follow-up, participants will complete measures of emotion-related impulsivity, self-harm, and suicidality.