Learn German: Ich mag lila, aber ich trage es nicht. - I like purple, but I don't wear it.

Use the verb mögen (here: ich mag) when you like a noun or a thing, like the color purple. If you want to say you like doing an action, you use a verb plus gern. For example, if you wanted to say 'I like wearing purple', it would be Ich trage gern lila.

Why doesn't the word aber change the word order in the second part of the sentence?

The word aber (but) is a coordinating conjunction that takes 'position zero' in a sentence. It connects two complete sentences without changing their structure. That is why the second part follows normal Subject-Verb order with ich trage right after aber.

Why do we use the pronoun es to refer to the color purple?

In German, when colors are used as nouns to talk about the color itself, they are always neuter words. Since it is literally das Lila, we use the neuter pronoun es (it) to refer back to it in the second half of the sentence.

Why is nicht placed at the very end of the sentence?

When you negate a complete verb action rather than just one specific word, nicht usually goes at the end of the clause. Here, it negates the entire action of wearing it, so it comes after the direct object es.