Confirm the dress code
Ask the venue for clear examples before buying clothes. Requirements may differ between ordinary shifts and special evenings. Check whether you can change on site and where personal belongings can be stored; photographs from an advertisement do not necessarily describe the working arrangements.
Prepare for the whole shift
Choose suitable clothing that lets you move comfortably and try your shoes beforehand. Bring a practical change if needed. Confirm what the venue supplies and what you must provide yourself, rather than making purchases on the assumption that everything will be reimbursed.
Discuss concerns beforehand
Appearance is only one part of the role alongside punctuality and communication. If a clothing requirement makes you uncomfortable, raise it before accepting the offer. A hostess position should have defined duties; different activities should not be introduced indirectly through an unexpected dress requirement.