Last year's spring bulbs can be all mixed in together presenting a problem to know which bulbs are which. If you have stored the bulbs over the summer in spare containers, or even the original containers, chances are this year when you want to re use them and plant out or into containers, its really hard to know what the bulbs are. Looking at them are they Daffodil, tulip, or crocus?
One way to at least half solve the problem if you cannot identify the bulbs is to sort them into sizes. Broadly speaking different types of bulbs are different sizes. The first image left shows a collection of bulbs tipped out of a container from last year. They are all healthy bulbs, ready to be replanted, and will provide a good spring display.
By sorting them into sizes such as the second image, which is all large bulbs, you have a prospect of planting similar types of bulbs together.
The larger of the bulbs are usually Hyacinth, followed by daffodil, and many tulips are largish bulbs. They are less likely to be Tulips because only a few varieties flower year after year. The smaller bulbs are usually iris reticulata , muscari, crocus and the smallest of all, snow drops.
After sorting into sizes plant in layers, largest at the bottom of the container to get the depth of soil it requires (ideally 3x the size of the bulb,) and keep putting in layers with snowdrops and crocus on the top.
The golden rule whatever you are planing is plenty of grit as in the image. Mix the grit with good compost. If the pot becomes water logged there is a risk the bulbs will rot and the extra grit helps to prevent this.