Soil pH Test Kits
Soil pH test kits give the gardener rapid results cheaply, which can mean big improvements to your garden.
I recommend soil pH test kits which use a special liquid that, when dropped onto a crumb of soil, changes color according to the degree of acidity or alkalinity of the sample. This can then be compared directly with a color chart to get the reading. Some kits of this type supply a small china dish to hold the sample while others use glass or plastic tubes. A low cost unit which uses strips of wax paper is perfectly satisfactory once you learn to juggle the folded paper and read it against the chart.
Soil test kits
You can find a whole range of these kits on Amazon - try these: soil ph test kits.
Be sure to buy a soil pH test kit that gives readings in direct pH figures, not in some mythical A, B, C system or in Roman numerals. Kits of the latter type are often sold cheaply or given away, but usually have to be used with a special product. Many of these products incorporate undesirable chemicals (such as aluminum sulfate used for acidifying) which you want to avoid.
Your first step in making a pH test is to get a uniform sample of the plot being tested. Don't use surface soil (roots rarely grow there) but dig down six inches. Avoid large lumps of organic matter unless you have a true organic soil such as peat or muck.
Soil should be moist for several days before you test it. (Drought affects the pH by killing off large numbers of bacteria, releasing organic acids which result in a false reading.) If the sample of soil used is allowed to dry for an hour or so in a shaded spot, it will give a clearer reading from soil pH test kits when the liquid is run through.