Infantry life changed drastically as England entered the pike & shot era of war. The New Model Army was composed of 12 Infantry regiments, 1,200 men each, 800 of which were musketeers, 400 that were pike. They all wore red coats, and the musketeers used Matchlock Muskets while the pike men had pike and sword (Plant). The Pike consisted of a long wooden shaft (10-14 feet long), topped with a steel spear point. Pikes were not meant to be used out of formation/close combat though, hence they had the sword. You could dismount a knight, then finish him off with your blade (Pike). Now the Matchlock musket was a complicated weapon, so I have posted a video by Kevin Kicks from the historical interpretation society's "History Squad" demonstrating the use of this weapon.

 

The New Model Army seemed to favor the Swedish Brigade tactics. Now I am no tactician, so I'll let you hear about the tactics from my source by David Plant,

"Swedish squadrons maintained the central pike block flanked by musketeers, but the formations were shallower than in the Dutch system, with ranks six men deep. This presented a broader front which brought more firepower to bear on the enemy. Like the Dutch, Swedish musketeers were drilled to maintain a continuous fire by use of the countermarch. However, Gustavus added the tactic of "doubling the files" when the enemy drew near, in which the rearmost ranks of shot moved up to fill the gaps between the frontline ranks, thus transforming a six-rank formation into three ranks. The front rank would kneel, the second rank would crouch and the third rank would stand. When commanded, all three ranks would fire simultaneously to deliver a devastating salvo, the "Swedish salvee". If the enemy stood firm, the musketeers would reload behind the shelter of the pikes to fire another salvo. As soon as the enemy faltered, the Swedish infantry charged forward to break them in hand-to-hand combat" (Plant)."

Below I have a video done by Matt Leiby, where he demonstrates the countermarch (method of continued fire with ranks) and also how Pike and Musket men would work together on a battlefield. To hear just about the items mentioned above, skip ahead to 18:38.

Plant, David. “Pike & Shot Tactics.” Pike and Shot Tactics, 2014, bcw-project.org/military/tactics.

Plant, David. “The New Model Army.” The New Model Army, 2007, bcw-project.org/military/new-model-army.

Image thanks to Mindhost. “From Swiss Pikemen to Swedish Mobile Artillery.” The Fencing Hindquarters, 18 June 2015, mindhost.tumblr.com/post/121839283227/from-swiss-pikemen-to-swedish-mobile-artillery.

“Pike.” Pike, www.medieval-life-and-times.info/medieval-weapons/pike.htm.