Many Japanese maples are perfectly happy to be in full sun all day, particularly the varieties with red leaves. Generally, the majority will do best with sun in the morning/early afternoon and some shading or full shade in the hottest parts of the afternoon and early evening. This will vary depending on your location and climate.
Japanese maples grow easily in Canadian Hardiness Zones 6-9 (USA zones are not equivalent!) however, it is possible to grow in 5b with some trees even surviving in 5a. Like any tree, it takes a year or two to be established in the landscape. At the lower cold extreme zones, some additional protection measures may be necessary. Also, in zones below 5a, typically trees are kept in containers and brought into sheltered areas over the winter period.
As for summer, in the hottest locations in Canada, trees should be situated where they will receive less direct afternoon sun and kept away from very hot, light coloured south or west-facing walls. Having an understanding of the climate you live in and the hardiness zone will go a long way towards the long term health of your tree.
Trees planted in the landscape, after a summer or two, are fairly drought tolerant, need little to no fertilizer, and pruning is minimal. Many Japanese maples can be pruned to sizes more appropriate to your requirements. If fertilizing is to be done, it should be applied early in spring only and should be of the slow-release variety. Organic fertilizers are always best. The nitrogen-phosphorous-potassium (NPK) ratios are lower with organic fertilizers, typically 4-4-4 or 5-3-4. Adding fertilizer is more important for container trees than trees in the ground because these container trees are depending on you for their growing needs.
DRAINAGE! Japanese maples grow in a variety of soil types but too much water will kill them! For containers, use the right potting mixtures, such as a mixture of fresh and composted barks, with some perlite. If you cannot find bark mulches, mixtures made for acid-lovers (coniferous, azaleas/roses/rhodos) is a substitute. The most important thing is well-draining. If planted in the landscape, mounding up the soil where you intend to plant the tree above the surrounding garden bed will assist with drainage. Adding some of that composted bark is also beneficial. Heavy clay soils are challenging, but if that's what you have you could add small rocks into the hole and bark mulch mix to help aerate the area somewhat and give the tree a good chance to avoid drowning during the wet times. This is also where ensuring the rootball is slightly planted above the overall soil grade is even more critical.
When it comes to watering, trees in pots will need more frequent watering than trees planted in the landscape. Smaller pots dry out faster than larger ones. During drought or unusually hot periods, trees need extra water. Again, container trees will require more than trees in the landscape. Mulch 2-4" to retain some moisture and protect the rootball from the sun/wind(and cold in winter).
Use the links below to find your hardiness zone from Plantmaps. You can also web search Government of Canada hardiness zones. Plantmaps show zones as being warmer than goverment listed zones and we tend to favour those based upon customer feedback and warming climatic conditions over the years.
Plantmaps:
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