Irregular Period

Ren • 21/Student/♈
Any tips to help regulate periods? I'm 21 and over the last year my cycle has become very erratic. It's getting quite annoy as I can pms for about 3 weeks out of every month. Currently my cycle is at 49 days, and I've been experiencing pms for about 2/3 weeks now. Please give me tips on how to settle the irregularity if possible. Thanks xx