Several practices to broaden participation and increase effectiveness of public science outreach have been found to be successful while leading >100 geoscience-themed hikes, bike rides and lectures as a volunteer in the last 10 years. Outreach opportunities included two-month long group bike rides across the USA and public engagements at Grand Staircase-Escalante National Monument in southern Utah, but most activities were in western Pennsylvania. Examples included certification training and continuing-education field trips with Pennsylvania Master Naturalists; lectures and indoor rock tabling in high schools; Road Scholar, Adventure Cycling, 9/11 National Memorial Trail and Bike the US for MS trips; a Pennsylvania DCNR Bureau of Forestry Caring for the Woods workshop; a Jeep jamboree trail ride; and geology-themed hikes and bike rides with Pittsburgh nonprofit Venture Outdoors. Popular themes included a series of hikes to waterfalls and guided group rides on each of the 25 major bike trails in western Pennsylvania. Offering and stamping a theme passport helped keep participants engaged. Docent-guided activities were preferred to self-led outdoor experiences. When participants were provided with access to online lectures about area geology before outdoor learning experiences, the depth and quality of science questions and dialogue increased greatly. Providing public online access to the thematic geoscience talks by sharing links in relevant trail friends and bike club groups increased science outreach tenfold. Relating underlying geology to landscapes and land use experienced by participants was especially engaging. Three tactics were found to be particularly effective in fostering participation and engagement in science outreach: 1. Providing adequate opportunity for participants to socialize, 2. Customizing outdoor learning experiences for existing groups including families, informal outing groups and communities surrounded by outstanding geologic features, and 3. Providing cool local fossils to participants who demonstrate exemplary learning or ask engaging questions. Regardless of the geoscience topic offered, public outreach leaders should look for opportunities to foster climate literacy and be prepared to respond accurately and concisely to questions about climate.