Getting a tax deduction for an allowed expense on your taxes is great. Making the mistake of claiming a deduction that is not allowed by the IRS can you get into trouble and a possible audit. For example, you can deduct the expense of a dinner with clients up to 50% of the bill only. If you claim more than the 50% allowed or you do not properly record the business purpose of the meeting, the deduction could be thrown out.
Travel is similar to entertainment were only the part of the travel that is business related can be deducted. If you take your family or your spouse with you and do things on your trip purely for pleasure, those parts of the trip cannot be deducted on your return.
Commuting costs are only allowed from one business location to another business location. The commute from your home to the office is not something you can deduct on your taxes.
Make sure your charity giving is to IRS recognized organization or the donation will not be deductible. And if you get something, like a night at the opera, in exchange for you donation, you need to subtract the fair market value of the benefit you receive from the donation that you claim.
And the IRS has made giving to charities without a proper record not something you can deduct. You could previously deduct small amounts of cash that you gave to charities. But now it is required that you have proof of the donation to get the deduction. So write a check instead of giving cash.