This all might look like much, but I swear it's not. The engineer is one of the most critical classes in the game, and are loved by their teammates. It's not hard to do it, but I wanted to give anyone who plays this weekend as much info as I could about the class. Just have fun.
FYI: He's called "engie" by most folks.
Your tools are:
Shotgun - Medium power than lowers depending on range. Slow rate of fire.
Pistol - Light on power, but more accurate and has better range than shotgun.
Wrench - Use this to "work" on your equipment (and other engineers' stuff).
Build Tool - Select this item (#4 in your list) to choose what you'd like to build. If you don't have enough metal, it will not show a picture of the item. If you do, it'll show a picture of a blueprint.
Demo Tool - Select this item (#5 in your list) to destroy anything you've built. This is handy if you built a sentry gun at the beginning of the stage, but now your team has pushed forward.
The things you can build:
Sentry gun - This is your bread and butter. It has three levels. The first is a single gun. The second is two guns. The third is two guns and a rocket launcher. Positioning of this is critical. Make sure it's pointed at the enemy or where they'd come from. Keep in mind that it only has so much range. Explore a few maps and you'll see where folks put them. Be creative.
Dispenser - This helpful machine you'll want to build next to your sentry. This machine will heal you and teammates and produce metal.
Teleporter Entrance - Self Explanatory.
Teleporter Exit - The opposite of the Entrance.
Tips -
1. As soon as you start a round build a teleporter entrance outside your spawn area, then run back inside to the ammo locker to get refilled on metal, then head out the door to where you'll be building your sentry gun.
2. Once you get to where you're building your gun, figure out your build order. If a BIG metal pack spawns nearby (only health and metal/ammo spawn), then build your sentry first. If it's a small metal pack or there isn't one, then build your dispenser first. Once you have a supply of metal, work on getting your sentry gun built and upgraded to level three. Once that's done, find a place to build your teleporter exit.
3. To upgrade sentry guns and repair your stuff, simply hit it with the wrench. You will have an on screen listing of your built equipment and it's health. You'll also have to occasionally rearm your sentry by hitting it with your hammer. Just keep in mind that rearming, repairing, and upgrading only occurs when you have a supply of metal. (The engie can carry up to 200.)
4. If your equipment gets sapped by an enemy spy you'll be notified via voice if you're far away or if you're close you'll see your equipment's health dropping. You'll also see them with blue electrical surges around them. Hit them with your hammer, but be fast, and then try to kill the spy.
5. You WILL have equipment get destroyed. It's inevitable. Just brush it off and build up again.
6. Shoot everyone with the shotgun who comes near you. If they bleed, keep shooting, they're a spy. If they don't, stop shooting.
7. A spy will look like other classes, but can't do their stuff. So a real pyro will shoot flames, a spy dressed like one can't.
8. If a spy keeps hitting your stuff, don't be afraid to ask if a pyro can stick with you until you get your stuff built. Pyros weed out spies immediately and kill them quick. They'll stand around your stuff and set everyone who walks up on fire. Friends don't burn...
9. Being an engie is all about support and management. If your team is pushing forward, don't sit back on your hands. If they've moved the front lines, move your equipment in relation, particularly your teleporter exit.
10. Right clicking will rotate your buildings. Look at the blue print to see which was the sentry gun will aim or which way your teammates will face when leaving a teleporter.
11. On maps when your team is defending you HAVE to get a turret setup quickly to defend whatever you're defending. On those maps there will be other engies so follow their lead. They might even give you tips on where to setup.
12. On maps when your team is attacking, the teleporter is critical. After that, a forward sentry can help your team establish itself.