If you use ramps, take a strap and connect the hook on one end around a rung of the ramp and the other end to something like a trailer hitch, hook under a bumper, or even the frame if needed. This will keep the ramp from sliding away from the bed of the truck as you load it. I am a BIG fan of using four straps, one per corner, to tie the bike down. Also, check to make sure the rungs of the ramp have serrated edges for the tires to grip. If they are smooth, it won't be pretty... Personally, I would not use a 2 x 8, 2 x 10, etc,... If the tires are wet, the boards are wet, or your shoe soles are wet, it won't be pretty...
I mostly use trailers, but I have been fortunate that my Dad has always had some and has let me modify them for hauling bikes. I now have a 7 X 16 enclosed trailer that I really like. But it is a big trailer if you are only hauling one bike! It would be nice to also have one of those little three rail trailers for when I just want to haul a few dirt bikes. I've even seen some that have the drop down beds so you don't even need ramps for the trailers!
The thing with a truck bed is height. Height is the enemy because IF you do fall, which is ALWAYS a possibility no matter how skilled you might be at riding up a ramp or how many times you might do it without any problems, the distance to the ground is going to make a HUGE difference. If you are sitting on the bike because you were riding it up, it will be hard to get clear of the bike if it does start to go over. It could EASILY land on you, which likely won't be pretty... For this reason, I would be more inclined to walk the bike up under power. I think you just have less chance of something going wrong, and if it does, you have a better chance of getting clear of the bike to avoid injury.
Wide ramps are best, but they do take up a lot of bed space. Two ramps side by side with a bit of space between will work, but again there is just more opportunity for something to go wrong. More than anything, getting the bed as low as possible before you start loading will be a BIG help. Height works against you.
Buy quality straps. Make sure the hooks come back on themselves a full 180 degrees if the straps don't have carabiners on the ends.
Regular ratchet straps with full 180 hooks
https://www.ratchetstraps.com/1-motorcycle-ratchet-straps
Carabiner style straps
https://www.ratchetstraps.com/1-ratchet-strap-with-stainless-carabiner
NEVER use straps with the S shaped hooks...
Trust me...
Some people will use the cam buckle style straps, and I did for a while. However, I no longer use them for anything that I cannot afford to have fall over or come loose. They have a bad habit of coming loose if they get wet. They also tear up the strap material over time because the teeth on the cam are digging into the strap material to generate the needed friction. I have had them wear through and break. Ratchet straps don't have this issue. It is also just easier to reliably tighten the ratchet strap.
If you don't use the carabiner type, because they are obviously expensive, then I recommend using cheap bungee cords with the hooks on each end to connect each end of the strap once the bike is set and the straps are tight. Just hook the bungee hook to the part of the strap hook where the strap attaches. This way, if the bike bounces and the suspension compresses, when the tie downs go slack, the bungees will keep the hooks under tension so they don't fall out of whatever you have them hooked to.
I am also a BIG fan of using soft tie downs. These are basically strap loops about 12" long that have the center of the loop sewed together, making a figure eight shape. This keeps the hooks off the bike and away from the bike so they don't scratch, rub, or bang into anything. They are very versatile in where they can be attached as well. Some straps will have soft ties built into them. They will be more expensive, but you tend not to misplace the soft ties
Soft ties
https://www.rockymountainatvmc.com/p/1010/24188/Rider-Cargo-Tie-Down-Extension-Straps
Carabiner straps with soft ties
https://www.rockymountainatvmc.com/p/1010/15453/Rider-Cargo-Ratchet-Soft-Loop-Tie-Downs-W-Carabiner
I bought several sets of 1" ratchet straps at Home Depot. There were eight straps per set I think. They had the full 180 degree hooks. I want to say they were $20-30 per set. The ratchet handles are rubber coated, which makes them easier to use. I use them for tying down anything from my kid's dirtbikes to my BMW 1200 GS. They work great. I have hauled a lot of bikes over a lot of miles and have never had any issues with them. I don't remember where I bought my soft ties, but I don't recall them being real expensive either.