Bring up the console with the ~ key. Type "player->" followed by a code below to activate that code. 
Get Level # - setlevel # 
Input player health - sethealth # 
Put Char in the cell ID - centeroncell [cell ID] or coc [cell ID] 
Set Flight- setflying 1 
Set Jumps - setsuperjump 1 
Be able to cross water - setwaterwalking 1 
Breathe underwater - setwaterbreathing 1 
Put Char in the exterior cell grid - centeronexterior [x,y] or coe [x,y] 
Create map image file for Xbox - createmaps ["filename.esp"] 
Get Gold - additem "Gold_100" # 
Set fatigue max - setfatigue # 
Input Maximum magic value - setmagicka # 
Put all entries in journal - filljournal 
All towns on map - fillmap 
Go 128 units from position - fixme 
Get faction reaction - getfactionreaction [faction ID factionID] 
help - help 
Show variables - showvars or sv 
Stop cell test - stopcelltest or sct 
Test cells - testcells or tc 
Test interior cells - testinteriorcells or tic 
Test models - testmodels or t3d 
Change AI - changeai or ta 
Change borders - changeborders or tb 
Change combat statistics - changecombatstats or tcs 
Change collisions - changecollision or tcl 
Change collision boxes - changecollisionboxes or tcb 
Change collision grid - changecollisiongrid or tcg 
Change debug text - changedebugtext or tdt 
Change dialogue statistics - changedialoguestats or tds 
Change fog of war - changefogofwar or tfow 
Show ownership and script name - changefullhelp or tfh 
Change God mode - changegodmode or tgm 
Change grid - changegrid or tg 
Change kill statistics - changekillstats or tks 
Change load fade - changeloadfade 
Change magic statistics - changemagicstats or tms 
Change menus - changemenus or tm 
Change scripts - changescripts 
Change stats - changestats or tst 
Change sky - changesky or ts 
Change texture string - changetexturestring or tts 
Change world - changeworld or tw 
Change wireframe - changewireframe or twf 
Change path grid display - tpg 
Show selected actor's group members - sg 
Show selected actor's target group members.- st 
Show scene graph - showscenegraph or ssg 
Move one to one - moto 
Change water - twa 
Change vanity mode - tvm 
Change script output - tso 
Change load fade - tlf 
Output reference information - ori 
Change lights - tl 
Show variables - sv 
Show animation - sa 
Reset actors - ra 
Purge textures - pt 

To add a specific item to your inventory first find the item name by looking in the Construction Set. Then simply type: 

"player->AddItem ITEM_NAME 1" in the console. 

For example, to get the Daedric Sheild, you would type: 

"player->AddItem "daedric_Shield" 1"