Changes in thinking skills are commonly experienced by older adults, though large variation exists. Such changes are one of the top concerns of people as they get older. Public perceptions of those changes could be used to effectively communicate with them about ways to improve their thinking skills. This study explored people's views about maintaining and improving thinking skills with age in a UK-wide survey completed by respondents aged 40 and over. Respondents answered an open-ended question "What would be one piece of advice you would give to someone to maintain or improve their thinking skills with age?". Responses from 3,165 individuals (95% of the survey sample) were analyzed using content analysis. Three main themes emerged: "keeping fit and healthy in mind and body; staying engaged with the world around you; and attitudes to prevent decline". Respondents thought that keeping physically and mentally active, being sociable, having a purpose in life and positive attitude, and preventative strategies could help maintain thinking skills. Adults aged 40 and over in the UK thought there are things that can help preserve thinking skills with age. The survey findings support previous research, extending the findings to adults in the UK. Understanding people's beliefs can inform better communication with them about what can benefit thinking skills. Effective communication should provide resources and advice in the same way other public health messaging is carried out (such as that regarding heart health).