Planning a Trip

I wanna go on a trip but I'm not sure where to go. I was planning on a summer trip but now that it's June I feel like it's kinda late to save up some money right now and plan a trip. I would like to be a person who just all of a sudden just get up and go but I too cautious that I feel I need to plan beforehand and be sure I'll be safe financially. I think the safest place to go is Los Angeles since my sister and her boyfriend lives there, I'll have a place to stay for free and a guide. 

I've been in LA for a little bit but never really been there long enough to take everything in. I know flight from Des Moines to Los Angeles is not too pricey so I think it would possibly be best to go and relax on the beach drinking the day away. I would actually consider spending a whole day at the beach to people watch and drink Coronas all day. Right now it just seems way too perfect to do. 

I was also thinking of planning a trip to the East Coast to visit my cousin but the thing about that is that it's a lot more expensive of a trip and I don't really know what to expect there.