First and foremost, you have to make sure that your invention meets the patent criteria. Depending on which country you are filing in, this might be a little different, not only because different products exist in different markets! Make sure your patent is novel, useful, non-obvious, and kept confidential, aka not in public knowledge. This can be hard if you’re excited about your invention or want to market it right away, but it is a crucial step to remember!
The next step is deciding whether you want to apply for the patent all on your own, or getting help from an attorney. It is not a requirement to get help from an attorney, unless you are filing for a patent in the US from overseas. Now it is a requirement to get help from a registered attorney. However, because patent applications can get complicated quickly, and because you’ll sometimes have to use particular wording in order for your application to be approved, it is a good idea for anyone filing a patent to get expert help.
Another thing you’ll need to do before you can make your patent application is to make sure your financial base is covered. How are you financing your invention? How are you financing the patent? These are really important elements of your product planning, because people may be curious to know about this in the future, let alone attorneys and those part of the path to your patent application. Ways of financing your patent include scholarships, grants, investors, and savings. Be clear on how you want to do this, as attorneys in particular may need to know this for your application.