Before starting to make the deck, you better determine the area where you have to build the stair case to meet the deck. If you want to save time and labour, you can simply buy pre-made stringers to build up the staircase. You might turn lucky and get the set which is of the correct height for your pool.
You better use pressure treated lumber for building the pool deck. Begin with making the under frame of the deck at the height of the pool. However, you should ensure that the height of the under frame is slightly lower than the level of the pool because adding the flooring boards to the frame later will also raise the level of the deck a bit and you have to account for it before hand.
You have to use 4-by-4 inch lumber for making the main supports of the deck. You need to dig 2-foot deep holes around the pool, insert the wooden posts into them and fill them up with concrete.
Then attach 2-by-4 inch posts in ‘X’ shape to form a cross brace and affix them with bolts and screws.
2-by-6 inch boards are to be used as the joists and attach them to the deck boards while laying them around the pool.
You will also need to make the railing for the stairs and the entire deck area to ensure no one falls off it. Use 2-by-2 or 2-by-4 lumber for making the railing posts.
Now you can attach the deck boards on the stair runners and raisers. Use stainless steel screws for this purpose.
Conclude your construction by attaching a top post on the handrails and the rail pickets. Make sure the pickets are closely positioned (not more than 3 inches apart) so that children might not get their heads stuck between them.