Original

You might start with a read of Wikipedia:Neutral point of view, and we think you'll find that it doesn't closely correspond to common notions of "neutrality". Basically, we are required to report the bad (negative) with the good (positive) – and the neither-bad-nor-good – in rough proportion to what's said in reliable sources, in this case largely major news outlets. If sources are widely critical of Trump, this article must reflect that. They are, so it does. This is Wikipedia policy.

If you think Wikipedia policy should be changed, this is not the place to say that. Wikipedia policy is not established at individual articles. You could try Wikipedia:Village pump (policy), although you are unlikely to be taken very seriously there without a substantial history of Wikipedia editing.

Any user, including you, is welcome to suggest a specific, policy-based improvement to any part of the article. That initiates a discussion which may yield a consensus for a change to the article. But general complaints about bias are not useful.

Some of the resources available to you are:

Wikipedia:Policies and guidelines is a good starting point for reading about, well, Wikipedia policies and guidelines.
Wikipedia:Teahouse and Wikipedia:Help desk provide general assistance to users. You ask a question about Wikipedia and experienced editors attempt to answer it. Sometimes you will be directed to a better place to ask the question. Of the two pages, Teahouse is more designed for newer users.
Wikipedia:Guide to addressing bias provides instructions on how you as an editor can address real bias on Wikipedia.
If you want to become more active in Wikipedia editing, Wikipedia:Adopt-a-user can set up a one-on-one "mentoring" relationship between you and an experienced editor.

My version

You have been pointed to this page because you have claimed that the Donald Trump article is, in some way, biased.

On Wikipedia, we are required to report the bad (negative) with the good (positive), and the neither-bad-nor-good, in rough proportion to what's said in reliable sources, which in this case are largely major news outlets. This is one of the five pillars of Wikipedia—a group of fundamental principles central to the function of this website. Since reliable sources are widely critical of Trump, this article must reflect that.

If you think that the policy should be changed, you could try Wikipedia:Village pump (policy), although you are unlikely to be taken very seriously there without a substantial history of Wikipedia editing. Wikipedia policy is not established at individual articles.

A general, non-specific claim of bias will not yield positive results, and will likely result in premature closure of the section. You are welcome to suggest a specific, policy-based improvement, one that is backed up by reliable sources (see WP:RS/P for a list of sources considered by the Wikipedia community to be reliable). This will likely initiate a discussion which may yield a consensus for a change to the article. This applies to any page on Wikipedia.

If you wish to do so, remember to always assume good faith, demonstrate good faith, and to be civil.

Some of the resources available to you are:

Wikipedia:Policies and guidelines is a good starting point for reading about Wikipedia's policies and guidelines.
Wikipedia:Teahouse and Wikipedia:Help desk provide general assistance to users. You ask a question about Wikipedia and experienced editors attempt to answer it. Sometimes you will be directed to a better place to ask the question. Of the two pages, Teahouse is more designed for newer users.
Wikipedia:Guide to addressing bias provides instructions on how you as an editor can address real bias on Wikipedia.
If you want to become more active in Wikipedia editing, Wikipedia:Adopt-a-user can set up a one-on-one "mentoring" relationship between you and an experienced editor.

Diff and reasoning

You have been pointed to this page because you have claimed that the Donald Trump article is, in some way, biased. Starts off with the reasoning behind why the editor was pointed here

~~You might start with a read of Wikipedia:Neutral point of view, and we think you'll find that it doesn't closely correspond to common notions of "neutrality".~~ Addressed elsewhere ~~Basically,~~ we are required to report the bad (negative) with the good (positive), and the neither-bad-nor-good, in rough proportion to what's said in reliable sources, which in this case are largely major news outlets. This is one of the five pillars of Wikipedia—a group of fundamental principles central to the function of this website. Important and relevant context If Since sources are widely critical of Trump, this article must reflect that. ~~They are, so it does. This is Wikipedia policy.~~ Unnecessary, addressed above

If you think Wikipedia policy should be changed, ~~this is not the place to say that. Wikipedia policy is not established at individual articles.~~ you could try Wikipedia:Village pump (policy), although you are unlikely to be taken very seriously there without a substantial history of Wikipedia editing. Wikipedia policy is not established at individual articles. Moved from above

A general, non-specific claim of bias will not yield positive results, and will likely result in premature closure of the section. Added to provide context ~~Any user, including you, is~~ You are welcome to suggest a specific, policy-based improvement, ~~to any part of the article.~~ one that is backed up by reliable sources (see WP:RS/P for a list of sources considered by the Wikipedia community to be reliable). Directly points the editor to RSP, which is a valuable tool ~~That initiates~~ This will likely initiate a discussion which may yield a consensus for a change to the article. ~~But general complaints about bias are not useful.~~ Unnecessary, addresed above This applies to any page on Wikipedia.

If you wish to do so, remember to always assume good faith, demonstrate good faith, and to be civil. Points editor to relevant policies

Some of the resources available to you are:

Wikipedia:Policies and guidelines is a good starting point for reading about~~, well,~~ Wikipedia policies and guidelines.
Wikipedia:Teahouse and Wikipedia:Help desk provide general assistance to users. You ask a question about Wikipedia and experienced editors attempt to answer it. Sometimes you will be directed to a better place to ask the question. Of the two pages, Teahouse is more designed for newer users.
Wikipedia:Guide to addressing bias provides instructions on how you as an editor can address real bias on Wikipedia.
If you want to become more active in Wikipedia editing, Wikipedia:Adopt-a-user can set up a one-on-one "mentoring" relationship between you and an experienced editor.