After creating a new article (using wikitext or VE editor), users add the interlanguage links by clicking into "add links" from the "languages" section in the sidebar. After connecting the new article with the rest of the languages, it may be a good opportunity to suggest the user what to translate next.

If the article is available in another language the user speaks, check that version of the article and look for links pointing to article which can be translated to the current language (i.e., articles missing in the current language). Then, one or more can be suggested to the user to start a translation.