Prescription Strength Banishing Rituals?

This might be a better topic for Ceremonial Magick, but seeing as how I am I more of a chaos magician myself, I am feeling compelled to seek advice from others who follow less traditional paths.

I'll be the first to admit I'm a somewhat sloppy magician. I've been practicing intermittently for about six years now. After a few years of being heavily involved in magick, during the past couple years I have done little aside from reading and research. Nonetheless, I have performed many rituals and cast many sigils over the years. I feel that I may have opened myself up to some negative influences/entities/what-have-you. I think I may have been followed by some entities when I moved to a new state several years ago, which had been plaguing me beforehand, and I also suspect I may have inherited some unfriendly spirits when I moved into my current residence also a few years ago. There is also a good possibility that I may be under magickal attack from a fellow magician whom had been a good friend until we had a somewhat nasty falling out about a year and a half ago. My life has definitely taken some turns for the worst since said falling out.

I perform the LBRP occasionally, though not nearly as frequently as recommended, and I may very well find that getting back into the habit of performing daily may alleviate my problems. In the meantime, however, I am looking for a more powerful sort of all purpose banishing to deal with any unintentional and even unrecognized negative influences that may be plaguing me.

If this were simply a matter of banishing specific entities I had intentionally summoned or created, I would feel more confident about crafting my own ritual. I may still do so, but I am hoping someone out there might have some suggestions. I'm basically looking for the magickal equivalent of a detox program or a hard drive reformatting, a single ritual to clean the slate and rid me of any entities I may have summoned, intentionally or not, as well as any other negative influences which may have attached themselves to me, whether or not I am currently aware of them. Due to the spontaneous and oftentimes intoxicated nature of my workings, as well as my general laziness in keeping records of them, I think it is quite likely I may well be haunted by entities I don't remember conjuring or things I have unwittingly attracted.

As I said above, I intend to start performing the LBRP daily and also want to start practicing magick more seriously, primarily to help deal with some personal issues; but I feel that all of this would be more effective if I could start with a blank canvas. Anyone have any experience with this sort of thing? Any ideas, suggestions, or rituals that you would recommend? Or perhaps better yet, any advice for crafting my own ritual with said end in mind?

When you say starting with a blank slate, a death-rebirth ritual comes to mind. I've done one before but i can not remember what i did exactly. It pretty much consist of psychodrama symbolizing death of the old self, and birth of the new self. Do whatever you can to create this, it is probably fairly individual for each person. If you search a bit you can probably find some information on this type of ritual. I really wish i could give you a example, but hopefully you can find what your looking for with what i'm giving you.

Download and Read "Psychic Self Defense" and maybe "sane occultism" by Dione Fortune I have never read them but they are suppose to be pretty classic books which i think could help you.

I may be a bit late with this but better late than never.
The Dion Fortune books suggested are excellent but the essence of all magickal self-defense is personal sovereignty and solidarity. In other words your level of self confidence, your sense of control of your life and of your space are paramount. If you are unable to banish your own lingering doubts and fears about yourself it will be impossible to permanently banish symbiotes and vampiric entities. If part of yourself is consenting to their presence on any level then the LBRP wont do you much good. It is somewhat akin to ending a bad relationship but letting the other person keep their key to your apartment.
Speaking as someone with extremely vast experience in this area I would say the most important thing you can do is meditate deeply on the health of your energy body. While in trance examine your auric field and chakra centers for leaks or weak spots. Ask yourself if you have made any subconscious agreements with non-physical entities. Be scrupulously honest with yourself when answering. Don't indulge in horror entertainment for the duration of the cleansing period, but surround yourself with imagery that makes you feel inspired, secure, confident. And absolutely do not hesitate to create your own spell.