How to increase magento speed

First Step  :- First Off All Delete all Cache And Reindexing Then Start Next Step .....

Open .htacess file of your Magento. Find this code in .htaccess file and Replace

Current Code :-

############################################
## enable apache served files compression
## http://developer.yahoo.com/performance/rules.html#gzip

# Insert filter on all content
###SetOutputFilter DEFLATE
# Insert filter on selected content types only
#AddOutputFilterByType DEFLATE text/html text/plain text/xml text/css text/javascript

# Netscape 4.x has some problems...
#BrowserMatch ^Mozilla/4 gzip-only-text/html

# Netscape 4.06-4.08 have some more problems
#BrowserMatch ^Mozilla/4\.0[678] no-gzip

# MSIE masquerades as Netscape, but it is fine
#BrowserMatch \bMSIE !no-gzip !gzip-only-text/html

# Don't compress images
#SetEnvIfNoCase Request_URI \.(?:gif|jpe?g|png)$ no-gzip dont-vary

# Make sure proxies don't deliver the wrong content
#Header append Vary User-Agent env=!dont-vary

Replace Code :-

############################################
## enable apache served files compression
## http://developer.yahoo.com/performance/rules.html#gzip

# Insert filter on all content
SetOutputFilter DEFLATE
# Insert filter on selected content types only
#AddOutputFilterByType DEFLATE text/html text/plain text/xml text/css text/javascript

# Netscape 4.x has some problems...
BrowserMatch ^Mozilla/4 gzip-only-text/html

# Netscape 4.06-4.08 have some more problems
BrowserMatch ^Mozilla/4\.0[678] no-gzip

# MSIE masquerades as Netscape, but it is fine
BrowserMatch \bMSIE !no-gzip !gzip-only-text/html

# Don't compress images
#SetEnvIfNoCase Request_URI \.(?:gif|jpe?g|png)$ no-gzip dont-vary

# Make sure proxies don't deliver the wrong content
Header append Vary User-Agent env=!dont-vary



Second Step :-  Find & Replace

Current Code

############################################
## enable resulting html compression

#php_flag zlib.output_compression on

Replace Code

############################################
## enable resulting html compression

php_flag zlib.output_compression on


Save .htaccess file.


Final Step :- 

After Complete  3 Step one time delete all cache and Reindexing.

Check Your Website Speed

Congratulation.