You'll have a long wait - it takes about 3 years to get asparagus crowns to crop.
It likes to be well drained, and well fed. If you've got claggy soil then dig a shallow wide trench and fork some grit into the middle. Place the asparagus crowns on that, and mix some manure or garden compost into the soil that you use to cover them. aim to leave the row slightly mounded, as this will help drainage and identify where the asparagus is before it shoots.
Do not harvest any shoots in the first couple of years. Cut the fern like foliage back to ground level in late autumn. Mulch with manure or garden compost after cutting to feed and keep weeds away.