Changing up Excersize!

WashingAwayThePoundsx

Daily I walk a fair amount.
Soon I am going to try to walk a 6 mile walk maybe once every 2 weeks. (besides when I go Theme parks).
I swim a lot, I try to go 2 times a day, I swim laps.
Is there anything I can do to intensify my work out, so I can burn more calories?
I am trying to go to planet fitness 2-3 times a week.
Soon I will be joining Swim Team, Practices are 3:15pm - 5:30pm everyday on the weekday.

I just want to find a way to burn more calories, and start to tone my stomach.

I notice a different in my thighs, they are slightly slimming down.

What are a few things I can do at home?

July 8th I am flying up to New Hampshire to visit family for a month. and I want to continue my diet and workout, but I feel like I will have to double time it due to the food I might be consuming.