I would suggest you find an attorney in your area that specializes in estate planning and call them to set up an appointment. As an estate planning attorney myself, I know most attorneys in this area will offer a free initial consultation. That will give you the opportunity to learn what options are out there and discuss the design of your own estate plan. A good estate planning attorney will educate you on the options and help you think of issues you may not have considered. (ie. How to avoid probate, plan for the event of your incapacity, asset protect the inheritances you leave to your descendants, etc.)
Once you show up for the consultation, the attorney will take it from there and guide you through the rest of the process. Good luck!
I suggest contacting an attorney who practices solely in the area of estate planning and has been doing so for several years. I know a lot of attorneys draft wills, but fewer attorneys draft them well. If you want increase your chances that you are well advised and that your documents are well drafted, consider hiring an attorney who is board certified by the State of Texas in the area of Estate Planning and Probate law, or a LLM in tax law. Talk to several attorneys and get a feel for who is the right fit for you. Ask how long they have been drafting estate planning documents, if they limit their practice to this area of law, and the cost for such service (at least a ballpark estimate). Once you feel comfortable with an attorney, hire them and let them guide you the rest of the journey. I wish you the best of luck.
The other lawyers have offered sound advice. You do not need to do much initially, other than to find an estate planning attorney and show up. As was pointed out, you want to deal with someone who specializes in estate planning, as opposed to someone that does everything in the world, and oh, yeah...will also do estate planning.
Your initial considerations will need to focus around what assets you have control over, who you would want to manage those assets in the event of your incapacity and/or death, who you would want to receive the assets in the event of your death, and how you would want them to receive the assets, (such as, in a lump sum, over a period of several years, etc). Other issues, such as probate avoidance, tax avoidance, etc., are also worth considering and discussing with the lawyer.
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