Whether you are growing tomatoes under glass or outdoors, the plants will continue to need a lot of attention. The essentials step with tomatoes, to get the flavour and texture right, is to feed and water regularly. By July the tomato plants will grow vigorously and its important to divert the plant's energy into fruits, not foliage.
Tomatoes are a vigorous plant and you need to keep them in check. Nip out all side shoots, and thin down, which means cut off leaves to add light for when the flowers turn to fruit and to restrict growth. Once the plant has set 3/4 flower trusses, stop off the growing point and keep pinching it out to stop the plant growing.
As the plant grows, it will need plenty of support and tie it in using soft ties. Be careful not to tie too tightly as the image on the left shows. The tie may be loose when first placed on the plant but as the stem grows, it can become tight which will damage the stem and wound the plant. For more about growing tomatoes follow the link which gives detailed advice about watering, feeding, nipping the side shoots and other tips for growing tomatoes successfully. Regular watering is essential for a good crop of tomatoes the plants should not be allowed to dry out.
Pinching out the side shoots is important because the plant is vigorous, if the side shoots are not taken off the plant will throw out more and more branches, growing thicker, and what you want is fewer leaves and more flowers. The short video shows how to identify and remove the side shoots also a handy guide "Success with Tomatoes" by the Sunday Gardener.
For successive crops you need to sow and plant successively, and in July there is still time to sow directly into the plot the last sowing of beans and peas. Salad crops especially the fast growing ones, (such as rocket and cut and come again lettuce) continue to sow through July, August, and September, depending on the weather.