I've actually listened to common jokes that exist in Chile regarding the two most common errors of Americans learning Spanish. What are they?
1) a really bad accent
2) inability to conjugate verbs
What can Americans do to overcome these two obstacles and not perpetuate the stereotype?!
Be humble and admit your accent is bad and needs to improve. Ask a native speaker how your accent is. Once you know the correct grammer or word, don't stop there. Even if you seem like a crazy person repeat the same word or phrase over and over again outloud trying to imitate the accent of a native speaker (maybe a recording). Let your tongue get acclimated to the new sounds.
You cannot cut corners. Memorize those conjugation patterns so you can form sentences and speak. Once you can do that, you won't have to memorize as much.