Our compost teas should be diluted 20:1 prior to usage, so a 1L mason jar of Crooked Farmz compost tea makes approximately 20L of ready-to-use product (about a 5-gallon bucket worth).
Municipal water is treated with anti-microbial agents like chlorine and chloramine, which is a good thing for us in terms of drinking water, but is less desirable in terms of a microbially-active compost tea. For optimal results, use untreated rainwater to dilute your compost tea 20:1. Using tap water directly is also fine, but the chlorine/chloramine present might discourage some of the microbes in the tea.

Use the diluted compost tea in a watering can or via a hose attachment to give the soil around the plants a drench and introduce the microbes directly to the root zone. Alternatively, you may spray on the leaves for a foliar application that may deter competing pathogens.
Freshness
Fresh compost tea is best used within 24-48 hours of delivery. If you will not be able to use it within 48 hours, it will stay fresh a little longer by keeping it in the refrigerator.
Like any fresh food product, however, you will need to monitor the freshness if you attempt to extend the 48-hour window. Smell the tea before it is used: it should smell pleasant, slightly earthy to neutral, perhaps with a slight hint of molasses.
If it stinks or has a negative smell to it, do not use the product on your plants as it has likely gone anaerobic and may harm them. (A little bit of a “tang on the nose” is acceptable, but a stench is not.)