In what ways was William Pitt responsible for British victory in the Seven Years war?

The Seven Years' War, also known as the French and Indian War, involved most of the great powers of Europe and resulted in significant land gains for Britain, effectively setting it up to become the massive world power it became in the nineteenth century. Pitt the Elder was instrumental in securing British victory in this war, for a number of reasons.
Although the Seven Years' War is dated from 1756, Britain had been at war with France prior to this and was indeed suffering heavily at French hands by the time Pitt became Leader of the House of Commons in 1756. This had, in Pitt's mind, largely been due to the leadership of Newcastle, who at that time held sway in the Commons. One of Pitt's first great successes was in forging an acceptable coalition with Newcastle in order to persuade the Commons to accept his leadership and his proposals for the war effort. Pitt curried great favor with the British people and was known as "The Great Commoner."
Pitt's first key steps in turning around the British defeat against the French were to engage with the Hanoverians and persuade them to go back on the agreements made at the Convention of Klosterzeven. This convention would have ensured that Hanover retreated from the war, leaving Prussia, Britain's ally, vulnerable to attack. Pitt successfully convinced the Hanoverians to return to war as a British ally. This increased the security of the British alliance on the continent, and also increased its number of available troops. Pitt also instituted a series of naval raids on France, although these had limited success at first.
Pitt's idea of utilizing Britain's great naval power to defeat the French was, however, a good one; in 1758 he developed this idea into a new strategy which used the British navy to pin down and capture factions of the French army, thus reducing the resources and troops available to the French. Pitt hoped to win victory in Germany and, subsequently, throughout Europe by ensuring the French had very limited resources in this area with which to fight back. This strategy proved successful in defeating the French land attack on Hanover, which had to be abandoned after the British defeated French forces at the Battle of Minden.
A number of French trading settlements at key points in West Africa also fell to naval attacks, inspiring Pitt to launch further attacks upon French islands in the Caribbean. This afforded the British a significant number of new ports in this area from which to attack if necessary. The great French hope at this stage of the war, the proposed naval attack upon Britain, had to be abandoned because Pitt's naval strategy in global waters was so successful, the defeat at Lagos leaving the French army too decimated to launch the planned attack—although, arguably, this benefit occurred more by luck than through Pitt's judgment.
Pitt also recalibrated the attack on Louisbourg which had previously been tried to no success; the British were able to capture this key city and subsequently Fort Duquesne, which gave them full control of the Ohio Country. This gave the British a good position from which to advance on French-held lands in Canada, ultimately capturing Quebec under the leadership of James Wolfe. When Montreal was captured in 1760, the war in North America was effectively won.
One criticism of Pitt was that his absolute refusal to offer the French any part of Newfoundland meant that the war continued for several unnecessary months beyond the capture of Belle Ile in 1761, a significant morale blow to the French and considered by many to be a sign that they would accept terms of surrender. However, Pitt was eventually able to conclude the war in Europe by increasing the number of British troops serving in the area, made possible by the fact that he had brought the war to an acceptable conclusion in North America.
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