I am 20 years old and looking to get my first travel card. I currently have a Chase Student Card(24mths), Amex Blue(14mths) and Citi TY Card(2mths). I am looking to apply for the SPG Amex this week with the 30K sign up bonus, and keep this card for main spend. However Since the card will be backdated it should give me a good bump in credit score. So I am wondering if I should also apply for another Card such as Chase Sapphire Preferred for the sign up bonus. I can't apply for Citi Cards since I just got my last card from them, but I was thinking if I applied for the SPG it would negate any bad effects from the CSP. I would most likely Cancel the CSP after one year. I have a lot of expenses coming up for school(tuition,books etc), so I should be able to meet the spend on both cards between this month and next. My CreditKarma score is currently 742. Just wondering what everyones opinion is? I know I am young and just starting but I also don't want to leave points on the table.

Would love some help