Collocational knowledge is central to communicative competence, but many second language (L2) learners struggle to acquire this aspect. To address this limitation, the present study investigated if textual enhancement and frequency manipulation would affect incidental learning of collocations from reading. Fifty-four first language (L1) Cantonese speakers read two English stories in which 12 adjective-pseudonoun collocations appeared either three or six times. The target collocations were coloured in red under the enhanced condition. Participants' attentional processes were examined using their eye-movements during reading and stimulated recall comments prompted by their own eye-movements. After reading, unannounced immediate and delayed posttests were administered. The results showed that increased frequency led to greater visual attention to the target collocations in terms of both duration and counts of eye-fixations. Increased frequency further led to better performances on the immediate form and collocation recognition tests. The effects of colouring increased first fixation durations, only when the target collocations appeared six times. Colouring was also linked to higher immediate collocation recognition and delayed meaning recognition and collocation recall scores. Stimulated recall comments revealed that participants noticed the pseudonouns and sometimes utilized their collocate adjectives to infer the meaning of the pseudonouns. The findings of this study demonstrate that textual enhancement and frequency manipulation may affect distinct aspects of collocational learning.