In a large container or directly in your gallon jug, combine the white vinegar and salt. Stir or swirl until the salt is mostly dissolved. It's okay if a few granules remain.
Add the liquid dish soap to the vinegar and salt mixture. Gently stir to combine, being careful not to create too many suds. The dish soap helps the mixture adhere to the weed's leaves.
Carefully pour the mixture into your clean spray bottle using a funnel if needed. Ensure the spray bottle is sturdy and suitable for garden use.
To use, spray the mixture directly onto the leaves and stems of unwanted weeds. Aim for a sunny, dry day for maximum effectiveness, as the sun helps to 'cook' the weed.
Avoid spraying desirable plants, as this mixture is non-selective and will harm any plant it contacts.