mat_phong 0
mat_mipmaptextures 0
cl_detailfade 0
cl_detaildist 0
r_drawdetailprops 0
mp_decals 0
r_decals 0
cl_phys_props_enable 0
cl_phys_props_max 0
props_break_max_pieces 0
r_propsmaxdist 1
g_ragdoll_fadespeed 10000
g_ragdoll_lvfadespeed 10000
ragdoll_sleepaftertime 0
cl_ragdoll_fade_time 0
cl_ragdoll_forcefade 1
cl_ragdoll_physics_enable 0
mat_queue_mode 2
lod_TransitionDist -1
r_lod 2
r_shadows 0
mat_hdr_level 0
mat_vsync 0
mat_dxlevel 95
tf_enable_glows_after_respawn 0

-Create a txt file named autoexec
-Post the commands in it
-Save the file, then press Save As
-Add in the name of the file .cfg and change Save as Type in All Files
-The last thing you need to do is to go to steam file, steamapps, common, Team Fortress 2, tf, cfg and paste the file

Just add this command in the txt file before making the cfg file:
net_graph 1 to activate / net_graph 0 to disable

These are the commands if you want to change something back.

mat_phong 1
mat_mipmaptextures 1
cl_detailfade 400
cl_detaildist 1200
r_drawdetailprops 1
mp_decals 200
r_decals 2048
cl_phys_props_enable 1
cl_phys_props_max 128
props_break_max_pieces -1
r_propsmaxdist 1000
g_ragdoll_fadespeed 600
g_ragdoll_lvfadespeed 100
ragdoll_sleepaftertime 5.0f
cl_ragdoll_fade_time 15
cl_ragdoll_forcefade 0
cl_ragdoll_physics_enable 1
mat_queue_mode -1 and 0
lod_TransitionDist 800
r_lod -1
r_shadows 1
mat_hdr_level 2
mat_vsync 1
mat_dxlevel 90
tf_enable_glows_after_respawn 1

Just delete the .cfg file.