good luck
Actually,although there are lots of ways for an undergraduate to learn foreign language, there's no shortcut to learn it .So no matter what kind of ways you've choose ,just persist and exercise everyday,and I recommend you software named Shanbay (扇贝in chinese) ,that is a excellent software with a mechanism that encourage you to learn english and share your progress to your friends,what's more,you can fully use a feature named XIAOZU,which can really inspire you and motivate you to learn more in such atmosphere
overall ,persistence is the only method for you ,and I believe that Shanbay will be the best assistant for you .
BTW I use the software for almost 400 days and I got 7.5 in IELTS examination without preparation even though I only got 470 in CET6 when I was a freshman,so come on and best wish