Set up data validation rules so a shared spreadsheet stays clean

Design data validation rules for the shared spreadsheet described below, for me to set up in {{tool}}, so the people who fill it in can only enter values the rest of the team can count, filter and report on.

Columns and what goes in each:
"""
{{columns}}
"""

Who fills it in and how (desktop or phone, how often): {{users}}
Lists of allowed values we already have (teams, product codes, statuses): {{allowed_lists}}
Problems we have had with entries so far: {{past_problems}}

Produce:
1. A table with the columns Column, Rule type (dropdown, whole number, decimal, date, text length or custom formula), Rule details (the exact range, list or formula), Input message (what the user sees on selecting the cell, under 15 words), Error message (what they see after a wrong entry, under 20 words, saying how to fix it), Reject or warn.
2. Step-by-step instructions to apply the first rule in {{tool}}, so I can repeat them for the rest.
3. Where to keep the dropdown lists, such as a separate sheet or a named range, and how to add a new value without breaking the rule.
4. A formula or conditional format that highlights existing entries the new rules would reject, so I can clean up what is already there.

Good here means rules that stop the problems we have had without making the sheet slow to fill in. For example, an error message might read: "Enter a date as month/day/year, such as 3/14/2026." This example shows the form only.

Use "reject" only where a wrong value would break a report or formula, and "warn" where an unusual value might still be right, such as a very large quantity. Do not invent allowed values: if a column needs a list I have not given, write [list needed] and describe what it should contain. Use only features {{tool}} supports; if a rule is not possible there, say so and suggest the nearest alternative. Keep the notes outside the table under 200 words.