Good SEO practices are definitely a nicer way to increase ones rankings in a search engine but at the same time the content and its usefulness for the user is of utmost importance and we have understood this vital thing time to time as in the competitive arena of internet, content and SEO both are of primary importance for improving the ranking. The fact is that if a user comes to our site for some information or even passing the time he should be compelled by us to visit again by offering something that he feels is unique in is perspective.Knowledge is power.
Its long process with time consuming, need to give at-least 3 to 6 month to reflect ranking on new website in Top 100 SERP result. More it depends upon the practice you perform , so in short there is no exact time frame to the ranking.