For a world trip, there are some things on which you should be sure about.
The first thing to be done is that make a list and choose the countries that you want to visit.
If you have a relatively short budget, then the countries engaged well are south America, Asia, parts of Africa, and Eastern Europe. But if you have considerable resources, then you can visit western Europe, primarily Switzerland, and Norway, North America, New Zealand, Australia, South Korea, and Japan, that are considered to be the expensive ones.
Though planning a round-the-world trip is a complex process, but budgeted flights can make it comfortable for you. Remember to plan a round-the-world trip with cheap flights & hotels as they are the means that made your trip comparatively less expensive than the first-class flights and followed by the regular flights. Nothing denies the fact that on a tour, a flight or ticket and hotels, i.e., accommodation, are the most expensive things. And if you are lucky to get these affordable, then it will make your tour less burdensome.
Many people prefer RTW tickets (also called round-the-world fare and is quite less), or others used a series of one-way tickets as they travel. The difference between them is the cost and flexibility. RTW is the round-the-world ticket that enables the tour with a series of flights that are linking the cities around the world and is reasonably priced but less flexible. However, one-way tickets are more flexible, but they are expensive.
Partnership airlines that are formed by the alliancing of airlines of some countries together, for instance, Oneworld Alliance (created by British Airways, American Airlines, Qantas, and Cathay Pacific) and Sky Team (comprised of Aero Mexico, Delta, Air France, and Korean Air) are providing excellent services to Plan a round-the-world trip with cheap flights & hotels
To book an economical plane ticket, what you have to do is to your search on sites, compare the deals provided by all the airlines available and select a suitable one according to your budget. Make sure to try to pick an airline with low-cost flights because only the visitation of each country is going to be much expensive, and some cities are much costlier than others.
After you are done with these bookings of flying. Think about transportation, food, and especially clothing because there will not always be summer that you can be traveling freely with just a little luggage. Last but not least, decide whether you are going solo or accompanied by the family and construct your planning according to that.