The aim of the study was to test an information booklet containing suggestions to parents on how to prepare their child for the first dental visit. Forty-five children and one parent per included child took part in the trial. Children were randomized in two groups; the information booklet was e-mailed to the parents of the study group. At the end of the visit, the dentist and the parent evaluated the child’s behavior through the Frankl Behavior Rating Scale (FBRS) and the utility of the booklet through a Likert scale. The children evaluated the pleasantness of the visit and the perceived pain through the Wong–Baker FACES^® Pain Rating Scale (WBFPRS). Parents evaluated the information booklet as highly understandable and useful. According to the dentist, informed children were more cooperative (FBRS median score: 4; IQR: 3.5–4) than the control group (median score 3; IQR: 2–4) (p = 0.013; Mann–Whitney U test). Children prepared with the booklet reported less pain (WBFPRS: 0.40 ± 0.82 vs. 1.42 ± 1.99; p = 0.034; t-test;) and tended to evaluate the visit as more enjoyable (WBFPRS: 1.1 ± 2.14 vs. 2.75 ± 3.43; p = 0.064; t-test) than unprepared children. The information booklet increases the child’s ability to cooperate during the visit and could represent a useful instrument for the clinical practice.