How can I block out the past?

How do I block out the past?
I want to forget everything...I think ill be better off if I do
Every time I try to though for some reason I find my self reminiscing =(

You can't. It would be great if we could do that. Maybe if you talked to a Counselor or Psychologist or some professional, they could help you work through whatever it is you're trying to forget. We all have things we want to forget (or most of us do).

put it all in a imaginary bubble and let it float out your life and out of existance...

You can't. ( I wish we could)
What you need to do is seek counseling. They can help you control unwanted thoughts and help you train yourself to think differently.

xox
Sika

you know what..seriously..you need to deal with those issues now, because if you try and suppress your issues they will only return later in life..youll be 25 and a emotional wreck...you have to talk to a therapist..to help show you how tto deal with those issues...they wont ever just go away...you just need ton learn how to manage..your bad past..issues...you can go at it alone...but you will have to learn how to handle those emotions..one day...SO WHY NOT DO IT AS SOON AS POSSIBLE-TO BRGIN A STRONG HEALTHY LIFE...you can do it...peace

The past is part of you. It's shaped you and made you who you are. Rather than trying to block it out, you might consider focusing those emotions into literature, poetry, or song lyrics.

Given my personal experience, you have to deal with past and find closure before you can fully heal yourself and move on.

 
We can't "forget" our past although sometimes our brain can cause remembrances of things or events to be hidden or blocked from our consciousness.

As far as trying to get those memories to stop popping up, I'd consider an approach of really looking at them and realizing that even in negative or "bad" situations, there can be found a "Positive" result or perspective. Look for that positive perspective and think about it. Maybe then those memories will start fading because they will have been dealt with.

Often times our subconscious puts things into our conscious mind because we have failed to deal with them. Once dealt with the brain will relegate them to "history" and not keep bothering you with them.