Hey 30 year old, you know that relationship you have right now? Work on it! Be open and honest with her. Like really open and honest, about everything. Kinks, shame, sins, wishes, doubts, don't let it pile up until you are 40, or your relationship will fail.
Hey 30 year old, Take note of the people that begin judging you like a cake that just came out of the oven, like 30 is some magical number of completion, and DELETE.
Hey 30 year old, Remember that your 30's can be the best years of your life so be grateful and make the most of it. Your parents are likely still healthy, you're done with school, your career is going in the right direction, and your body doesn't ache yet
Hey 30 year old, motivation won't cut it, develop discipline