There’s no fool-proof way to correlate how much you drink to what your BAC (blood alcohol concentration) is.
It all depends on your body’s ability to absorb alcohol and this depends on many factors including body weight, sex, metabolism, age, how much you’ve eaten and when, and the type of food you’ve eaten.
The more you drink, the higher your blood alcohol level and the stronger the effect of the alcohol on your reflexes and decision making.
Alcohol is absorbed into the bloodstream where it is transported around the body until the liver can metabolise it. Larger people can be affected less, or more slowly, than smaller people. In a smaller person, alcohol is concentrated into a smaller area due to their smaller body mass, and so it has a greater effect.
Once alcohol is in your blood stream, your liver is responsible for removing it. There is nothing you can do to make this happen any faster. If your blood alcohol level is above .05 and you want to drive home, the only thing that will get your blood alcohol level below .05 is waiting for your liver to do its job.
For most people, alcohol is removed by the liver at a rate of about one STANDARD drink every hour. A standard drink is 100 mL of wine, 285 mL of full-strength beer and 30 mL of spirits. More information can be found here: https://alcoholthinkagain.com.au/Alcohol-Your-Health/What-is-a-Standard-Drink
Remember that your blood alcohol level will continue to increase for a while after your last drink as the alcohol is absorbed.
If you think you have had too much to drink, you probably have and shouldn't drive.
The only way to really know your blood alcohol level is to use a breath tester. Many hotels have breath testing units and a personal breathalyser is a useful device to provide assurance that you are below 0.05.
A range of personal breathalysers starting from $149 can be found here: https://www.andatechdistribution.com.au/collections/personal-breathalysers/