Using the of the entry, select next to the vandalizing edit. Do nothing in the edit window: just save/publish the changes after confirming that the edit you are making is the one you want to make.
There two places to specify preferences.
Longtime Wiktionary contributors don’t like made-up words. So they have this RFV process to kill off made-up words. What to do? Well, by working within the system, you can get your word added… the key is finding print citations. (Anything “durably archived” qualifies, but citations from actual books are by far the best thing to use.)
Well, we are here on the internets, right? Using a resource such as Google Books or Amazon can quickly give you exactly what you need. Another great resource is Wikisource, where searching on a word will give you the texts that contain it (use , not .) You can also go to “regular” Google itself and add “site:gutenberg.org” to your search to find public domain texts.
For each contested sense, you’ll need three print citations. Figuring out the format is hard for the first one, but easy thereafter. Year, author, title, link, text.
If you speak only English, there isn’t much point in using the “Tower of Babel”. But if you do speak more than one language, there is probably someone here who wants your help checking a translation or something. The Wiki way of finding such people is through the “Babel” templates. So, it is requested that you add it. For example, {{#babel:no|en-3|nn-3|da-2|sv-2|de-1|es-1|eo-1}} identifies a person as knowing eight languages, the first five of which they are pretty comfortable contributing in.
For each, use the ISO 639 code for the language, an ASCII hyphen character, then a level number from 1 to 4 (for your native language, leave off the hyphen and number).
Note that the order you put them in determines how they appear on your user page. Most people just list them best to worst. See Wiktionary:Babel for more details.
If you find yourself patrolling Special:RecentChanges a lot, you will want “Enhanced RecentChanges” selected in your preferences. But most regulars have given up on it, preferring instead to use Vandal Fighter or Vandal Proof.
See Help:Customizing your skin for CSS and JS methods of customizing your skin.
Several “bookmarklets” are available for Wiktionary purpose. See the subpage /Bookmarklets for more info.
Browse for Wiktionary-related Firefox add-ons.
Amazing things are possible using CirrusSearch. See mw:Help:CirrusSearch.
Examples include fuzzy text searches and searches for entries with templates, entries with regular expressions in the wikitext, entries in categories and in subcategories of other categories, and combinations of these and others.
Search can be used to create ad-hoc lists for making changes to entries, to clean up errors, or to provide missing content, etc.
PetScan is a handy tool to find entries in more than one category, or in one category and not another.