Sensation-seeking is the seeking of varied, novel, and intense experiences and the willingness to take risks to engage in these experiences. Sensation-seeking is associated with engagement in risky behaviors but questions remain concerning the role of within-person variability in sensation-seeking. We use data from a 21-day daily diary from 167 participants (mean age = 25.37, SD = 7.34) to test within-person associations between sensation-seeking and both alcohol use and self-reported risk-taking. Participants also reported the riskiest behavior they engaged in each day, allowing insight into the perceived risky behaviors that participants take during daily life. Results indicate those days of higher than usual sensation-seeking are more likely to be days on which alcohol is consumed relative to days of no alcohol use. The association between day’s sensation-seeking and alcohol use does not extend to the quantity of alcohol consumed. Risk-taking is higher than usual on days of higher than usual sensation-seeking. Using network science tools, we reduce 2,490 self-reports of the day’s riskiest behavior to 20 communities reflecting a wide range of risk domains, including social, school, work, and drug use risks. Creating a risk-taking diversity score based on the identified domains of risk behaviors, we find that trait sensation-seeking is positively associated with greater diversity in the types of risks reported. In summary, we observe that sensation-seeking and both alcohol use and other risky behaviors are associated at the within-person level, and provide insight into the types of risks taken during the course of daily life.