There are a few stages to the patent application process. It usually takes at least a few years to go through all the stages. The later stages are the most expensive so most people try to delay them as long as possible.
In the time before you officially file a patent application, make sure to keep your invention secret. This is really important. If you don’t keep it secret, you may ruin your chance of getting a valid patent. An experienced patent attorney can tell you more about what you can and can’t do at this stage.
Once you’re ready to prepare a patent application, you need to know which aspects of your invention can be patented. An experienced patent attorney can help with this.