Are you talking about gladiola or lilies or ? Why are you turning over the soil where you have bulbs? Normally they would be in a border where weeding would be adequate disturbance and would not interfere with bulbs. Depending on the weather and the bulb in question you may or may not still have viable bulbs. It is always nice to add a few new ones though. If you dig up bulbs and they are firm with fresh roots growing strongly you should be alright. Just replant them immediately.

As Scotsgran implies, it depends what kind of bulbs you're talking about - if its daffodils, for instance, when you turn the soil over in March, you'll clearly be able to see where they are, same with tulips and all the spring bulbs. But if they're summer ones, like lilies, you won't know where they are - these you'll have to remember where you've planted them and go very carefully. Same goes for certain herbaceous perennials, some of which disappear completely during the winter.

The most popular kind of bulbs such as daffodils, tulips, crocuses, etc flower year after year and don't need to be touched unless you specially want to move them. In fact many will multiply and make a bigger display as the years go on. Most people just leave them alone.

Not sure if this is the sort of elementary answer you needed in case you have planted bulbs for the first time ever.