Wikipedia:Misuse of the sandbox

The sandbox is a page where users can make test edits and preview them. Users have more freedom when editing the sandbox; users can post content there that would normally violate policies. However, there is still a lesser degree of editing restrictions in the sandbox; for example, users may not post legal threats or libelous/defamatory material. Such content may be considered vandalism and removed at any time, and repeated infractions can lead to a block.

Removal of the header
The following lines that make up the sandbox header should not be removed.

The header contains important information. Without the header, new users may not know what is and isn't acceptable. Without it, they may not know that their changes will not be permanent, and it may deter new users when they discover that their edits are missing.

The removal of the sandbox header is still considered unhelpful, even though it is automatically replaced by a bot, often within seconds.

Copyrighted content
Posting copyrighted content without permission in the sandbox, or anywhere else, is unacceptable, and may even lead to a block.

Personal attacks and harassment
Personal attacks of a user, a person, or anything are unacceptable in the sandbox, or anywhere else. An uncivil comment on the sandbox could easily deter new users, who could have become useful contributors. The sandbox should not be used to harass users or people either (i.e. by posting personal information about someone you know, or another Wikipedia user).

Such edits will most likely be reverted by someone, or get overwritten by other experimenting users (or in the case of personal information, suppressed in accordance with the oversight policy). Repeated posting of personal attacks and/or harassment on the sandbox, or anywhere else may lead to a block or even a ban.

Redirecting the sandbox
The sandbox should not be redirected, as it may cause confusion for experimenting users and may lead new users to make test edits on the page the sandbox is redirected to. Instead, experiment with redirects in your user sandbox.

User warnings and block notices
User warnings and block notices should not be added to the sandbox, as they may lead new users to believe they have done something wrong, or they have been blocked.

If you need to test a warning or block template, please consider using one of the template sandboxes: X1, X2, X3, X4, X5, X6, X7, X8, X9, X10, X11, X12, X13, X14, X15, X16, X17, X18, X19, X20, the Template sandbox, or alternatively User talk:Sandbox for user warnings for user warning or block templates. You may also consider creating your own personal sandbox if you have an account, however, it may not be used to post vandalism, hoaxes, or fake articles to, otherwise, it may be deleted at any time in accordance with Wikipedia's criteria for speedy deletion, particularly, the criterion governing pure vandalism and hoaxes. It is also important to note that it may not be used as an attack page either, or it may be deleted at any time in accordance with speedy deletion criterion G10. Continued disruptive editing or disruptive (sandbox) page creation, whether vandalism, attacks, or any other behaviors considered by Wikipedia policies to be disruptive will result in a block.

Creating your personal sandbox
Some of the above do not apply if you create your own personal sandbox at User:(your username)/sandbox. However, in your own personal sandbox, you still shouldn't post non-free copyrighted or defamatory material, personal attacks/harassment, or writings, information, discussions, and/or activities not closely related to Wikipedia's goals. The addition of promotional material is not acceptable either as Wikipedia is an encyclopedia and not a place for advertising or promotion; use Template:Db-spam to deal with such cases. In your own personal sandbox, you are most likely not going to get into edit conflicts since you are most likely the only user editing it.

Note: If you do not have an account, you can create a sandbox in your user talk space instead of your user space.