How do i transfer music from itunes to iphone

Question

how do i transfer music from my itunes account to my iphone? I was able to sync purchases from my phone to itunes, but can't move my music to my phone.

Answer 1

This series of posts was very helpful to me in fixing a problem I had encountered (apart from the various rude comments made by those who seem to have no patience with users who do not have their skill level...).  The problem that I had is as follows -- at least I think this was the problem. 
For some time I had been managing my music on my iPhone manually.  That is, I simply dragged and dropped the music I wanted to my iPhone from my laptop using iTunes.  Then, suddenly (it seemed to me) all of the music I had put on my iPhone seemed to disappear except one album that I had recently bought.  I kept putting music on the iPhone, and it would work fine, and then it would disappear again.  I looked through manuals and settings and couldn't seem to figure this out.  Now what I've determined is that iTunes must have changed something in a more recent version that deletes music that is not "synced" with each new sync of the phone.  (dragging and dropping had worked on my iPhone and iPod for some years previously... but i think with an upgrade of the iTunes software things changed.)
So, following the suggestions in this discussion, I went to iTunes with my phone plugged in.  Clicked on the device (i.e., my phone).  From the Music tab (at the top), clicked on Sync Music.  (Previously I had not followed through on this step, because there was a warning message that said all the content on my phone would be erased -- technically false, because it would only erase music on the phone, not everything.)  But when I did click on the Sync Music, accepted the warning, and then clicked on "Selected playlists, artists, albums, and genres," there then appeared a very nice set of checklists that allows for on-going management of music on the iPhone.  (I didn't know about this checklist because it didn't appear...  I had thought that "checking" was something that was to be done from the main music menus...)
Anyway, the system of checking playlists, albums, etc. is quite nice for managing music on the phone, because my phone will not hold all of the music that I own, so I can update the phone by syncing so that it holds only that portion of the library that I want to use at the moment.  (Sometimes I'm listening to the Blues on a daily basis, sometimes to Beethoven...) So, even though this discussion didn't tell me all of this, it did give me the lead that I needed to get there. 
So, as a comment to our rude fellow commentators here:  I've been working with Macs and Apple equipment for over 20 years.  I don't go back to re-read all of the manuals every time I upgrade software.  And when Apple doesn't tell you that they've changed something in their software that invalidates a procedure that you've been using for years, it can look very strange.  Then, when you do go to the manuals to search for the problem, rarely do you find (at lease rarely do I find) any explanation that a new procedure is in fact a new procedure that invalidates an old and trusted procedure.  This is a problem that I run into periodically, and it makes me feel stupid, and it may make my questions posted to forums seem stupid to others.  Other users are new to Apple, its software, its devices, and may have other reasons for asking simple questions.  If the question is so simple to you that you don't want to waste your time with it... well... then don't.  But don't insult other people who need help.  Leave it to those who can take the time to be courteous and helpful.  In this case, even though I'm a long-time user, it was responses to really basic questions that led me to the fix for a problem that had been annoying me for weeks. 
So, thanks to those of you with simple, basic questions, and thanks also to those of you who helped.