An LLC (or any other entity for that matter) cannot shield you from your own personal negligence. If you act negligently, you can be sued personally, whether or not you have an LLC. As a shield from negligence for a sole proprietor, insurance is always the best first line of defense.
If you elect to be taxed as an S Corp, your LLC may be able to shield you from some self employment taxes. You need to pay yourself (via payroll from the LLC) a reasonable wage, and can take profits in excess of the reasonable wage as distributions which aren't subject to self employment taxes. You and your accountant will need to determine what's a reasonable wage, but it can't be ridiculously low.
For the LLC to "work" you need to keep your personal finances and the LLC's finances absolutely separate and distinct. No buying groceries with the LLC debit card, no paying for the kids' soccer camp from the LLC checking account.
As far as the tax "savings" go, you should plan on paying your accountant a little more to manage your finances a bit more closely, since you have admitted that you are unlikely to be able to do it efficiently yourself. You also need to budget for organizing the LLC and paying annual filing fees, business licenses, etc. Then you have to weigh the net savings after all of those costs against the pain in the ass factor of having more paperwork and procedure.