All blocks drive from the elbow. The elbow should lead the block in the direction it is to go. Over time the blocks can harden and become actual blocking strikes. Description below is from LAS.
Upward: LH across body at stomach level, arm in 90 degree angle, keeping arm parallel with floor raise the block up. Stop upward movement just above the forehead. LH closed fist palm facing out.
Upward Angle: LH across body at stomach level, arm in 90 degree angle, punching your fist upwards raise the block up on 45 degree angle to left. Stop upward movement just above the forehead. LH closed fist palm facing out.
Outward: LH across body at stomach level, arm in 90 degree angle, in an arcing motion moving the arm anti-clockwise bring the arm up and across the body and face. Finish the block just opposite the right shoulder. LH closed fist palm facing in.
Inward: RH arm in 90 degree angle across body, LH lift hand up by your ear, elbow straight up until triceps area is parallel with floor. LH closed fist, palm facing in. Drive the block across the body to the right shoulder and stop. As you bring your LH across pull your RH back to your ribs. LH fist should be in line with your shoulder and at eye level, your elbow should be inline with your centreline.
Low down: Bring LH up in closed fist to about 3 inches out from your left ear. Drop LH across body on angle and finish just outside LL. Keep the arm bent as per crescent defence. LH closed fist, palms facing in. This is actually two blocks, first blocking the head strike, then blocking the kick.
Cover: Bring your hand up around the side of your head and place your palm on the back of your head. On your cerebellum. Your elbow should be pointing straight forward. Chin tucked down. Your fingers should right round the back of your head so the gap is minimised.
Broken Wing: LH straight up in the air above head. Bring down across the body from the head to the belt level swinging arm out to left side in an upside down outward block. Finish with arm on the angle out to the left side bent at the elbow, closed fist palm in.
Down to the belt: LH straight up in the air above head. RH on ribs. Bring down across the body from the head to the belt. Finish with arm horizontal across, closed fist palm in, blocking at belt level across the body.
Cross Low/High: This can be performed with closed fist or open palm. Cross arms at wrist level, usually RH on top. Arms bent at elbow slightly, Block can be low or high. Block forms a X shape.
Monkey Block: LH parry inwards at waist height, RH inwards inside hammer fist block meeting in the middle. Your LH should be blocking in the forearm of your RH.
Fan Block: RH inside parry, bring LH up in and outward open hand block clearing the RH inside parry. Same applies to open them up or close them off (LH parries inwards, RH clears)
Wave block: Outwards parry with LH, lift left elbow as the RH comes under the attacker’s arm and outward parries to your right (like waving)