Easy. First, research on the places you wanna go. You can use wikivoyage.com or wikitravel.com, tripadvisor, etc to zero in on the parts of Thailand you wanna go. If you are newbie, its easier to visit places with alot of tourists (bangkok, chiangmai, huahin, phuket, etc), since the locals there are more likely to be able to speak English and the hotels and transport network is well developed.
For each area/city, decide on the attractions you wanna visit. Goto google maps and create a custom My Map and locate all the places and attractions you wanna visit. Download the map KML to your phone. Download a copy of Triposo or other travel guide to your phone as well for travel info.
Book your tickets and hotel (i use agoda or booking.com for hotels, but there are many equivalent sites).
Make a packing list, and try not to overpack. Keep everything to just a single 40L carryon backpack. My pack is usually 3.5-4.5 kg, including the backpack, depending if I'm going to a hot place, cold place, and the bag I happen to be using. This allows you to travel light and fast. People struggling with multiple bags become easy targets for pickpockets and snatchthieves.
On arrival, get a data SIM card for online access without having to rely on Wifi hotspots.
Lastly, buy travel insurance, use a money belt, stay alert, avoid dark lonely places, and don't carry your wallet or passport in your back pocket.
Hey guys, so i had been thinking of going backpacking to SEA but i'm unsure of how to go about planning. As of now, I think i would be backpacking solo. Any tips for a newbie?

Thinking of backpacking to Thailand for 1-2 weeks