Consider using synonyms for each word you use, even if the word seems unimportant. The word "lighted" means one thing, while "illuminated" is similar, but has slightly different meaning. It's more formal and it has more syllables, for example. The former might be better for a poem intended for children.
Read your poems aloud as you compose and revise. The sound of the words in context is important poetry. Further, you will often hear good and bad things that you don't get just by seeing the words on the page. This also allows you to take advantage of alliteration: the felicitous repetition of sounds. ("She sells seashells by the seashore.")
Bury the meaning of your poem deeper in different drafts of the poem. If you're writing a poem about a sad childhood, try describing the situation less specifically so the poem will have more specific appeal to more people. Conversely, try a draft of the poem in which you are blatant in the meaning. Decide which you like better for the final draft.
Mimic the poetic forms that have been used by other poets. Great poems have been written in the form of the laundry list, the "Dear John" letter, TV listings; just about any form can be made into a poem because they communicate meaning that you can rearrange for your needs.
Read as much as you can for inspiration and don't restrict yourself to poetry. (Obviously, you should read lots of poetry, too.) Not only will you get specific poem ideas, but you'll be able to improve your other poems because of your wider understanding of culture. In an interview with "Poetry Daily," the poet Andrew Hudgins cites a number of influences, Robert Lowell, Robert Frost and the Bible among them.
Perform your poems at open mikes or other occasions and make note of the lines and images that earned the biggest audience reaction. You shouldn't, however, change everything to fit the audience's desire. In the end, the poem is yours.
Communicate with local poets to further immerse yourself in the world of people who read and write verse. After all, poetry started out by being passed to others orally. It is also enlightening to write poems with others. See what happens if you just trade lines back and forth. Quite often, an order emerges out of the seeming randomness.