The best months to plant the bulbs are April and May.
First find a nice sunny spot in your garden or on your balcony. Make sure the soil is well-drained, to prevent bulbs from rotting. You can mix the soil with compost (especially if you have heavy clay soil or soil that stays wet), to ensure good blooming. The soil will have to be loosened prior to planting. This will make the soil airy. The bulbs will love this! Also take away weeds. This will save you a lot of frustration during spring and summer.
Make holes in the ground: 5 cm deep and 15 cm apart from each other. Make sure the bulbs have enough space. (Contrary to seeds, you can’t replant the bulbs later.) Put a bulb in each hole, place them pointy side up. If there is no pointy side, look for where the roots come out: that end goes down. Cover the holes.
After planting, water your bulbs well. Make sure the soil is always a bit moist. Regularly remove the weeds that grow between your home-grown flowers.